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Schedule III - Real Estate and Accumulated Depreciation and Amortization Under Operating Leases - Table 22 (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended |  |  |
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | $ 5,236,251 us-gaap_RealEstateGrossAtCarryingValue |  | $ 4,686,844 us-gaap_RealEstateGrossAtCarryingValue | $ 4,145,368 us-gaap_RealEstateGrossAtCarryingValue | $ 3,531,845 us-gaap_RealEstateGrossAtCarryingValue
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 513,175 us-gaap_RealEstateAccumulatedDepreciation |  | 418,136 us-gaap_RealEstateAccumulatedDepreciation | 333,778 us-gaap_RealEstateAccumulatedDepreciation | 270,621 us-gaap_RealEstateAccumulatedDepreciation
Operating Lease |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 26,000 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,787,519 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,915,411 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 536,524 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,785,779 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 3,414,698 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 5,200,477 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 511,702 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember |  |  |  |
Operating Lease | Sunco Baltimore, MD 4 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 368 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,647 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 368 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,647 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,015 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 94 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD4Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Baltimore, MD 5 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 523 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,809 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 523 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,809 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,332 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 192 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD5Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Baltimore, MD 6 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 542 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,054 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 542 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,054 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,596 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 117 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD6Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Baltimore, MD 7 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 455 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,122 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 455 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,122 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,577 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 145 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBaltimoreMD7Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Bel Air, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,376 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 620 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,376 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 620 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,996 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 35 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBelAirMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Bethesda, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,414 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,347 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,414 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,347 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,761 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 92 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoBethesdaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Centreville, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,753 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 697 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,753 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 697 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,450 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 40 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoCentrevilleVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Chantilly, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,472 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,831 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,472 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,831 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,303 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 125 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoChantillyVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Dale City, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 639 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,461 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 639 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,461 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,100 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 140 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDaleCityVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Dumfries, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 387 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,364 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 387 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,364 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,751 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 135 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoDumfriesVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Edgewood, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 823 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,073 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 823 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,073 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,896 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 142 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoEdgewoodMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Frederick, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 940 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,860 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 940 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,860 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,800 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 106 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoFrederickMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Gaithersburg, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,027 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,073 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,027 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,073 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,100 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 142 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGaithersburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Glen Burnie, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 804 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,647 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 804 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,647 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,451 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 94 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoGlenBurnieMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Herndon, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 707 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,792 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 707 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,792 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,499 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 102 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoHerndonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Joppa, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 862 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 174 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 862 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 174 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,036 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 12 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoJoppaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Manassas, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,230 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,521 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,230 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,521 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,751 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 87 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Manassas, VA 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 746 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,434 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 746 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,434 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,180 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 82 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoManassasVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Odenton, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 668 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,780 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 668 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,780 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,448 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 158 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOdentonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Owings Mills, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,337 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 911 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,337 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 911 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,248 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 52 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoOwingsMillsMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Parkton, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 397 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,151 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 397 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,151 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,548 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 122 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoParktonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Pasadena, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 407 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,492 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 407 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,492 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,899 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 85 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Pasadena, MD 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 591 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,509 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 591 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,509 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,100 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 143 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPasadenaMD2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Perryville, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 601 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 3,778 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 601 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 3,778 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,379 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 215 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoPerryvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Randallstown, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 746 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,715 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 746 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,715 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,461 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 98 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRandallstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Reisterstown, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 649 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,354 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 649 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,354 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,003 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 134 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoReisterstownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Rockville, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,996 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,054 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,996 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,054 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,050 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 140 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoRockvilleMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Severn, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 765 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 3,139 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 765 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 3,139 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,904 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 179 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSevernMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Sterling, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,540 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,461 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,540 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,461 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,001 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 140 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Sterling, VA 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,356 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,095 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,356 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,095 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,451 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 62 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoSterlingVA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Timonium, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,356 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,598 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,356 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,598 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,954 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 109 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTimoniumMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Towson, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 630 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,771 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 630 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,771 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,401 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 189 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoTowsonMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunco Warrenton, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,802 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,703 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,802 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,703 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,505 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 154 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWarrentonVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Sunco Woodbridge, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 678 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,664 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 678 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,664 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,342 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 182 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SuncoWoodbridgeVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunshine Energy Kansas City, MO |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 517 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 720 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 517 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 720 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,237 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 157 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyKansasCityMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Sunshine Energy Neosho, MO |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 352 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 775 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 352 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 754 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,106 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 148 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunshineEnergyNeoshoMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 18 years |  |  |  |
Operating Lease | SunTrust Albany, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 287 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 890 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 287 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 890 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,177 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 91 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlbanyGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Alexandria, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 2,735 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 732 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 2,735 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 732 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,467 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 75 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlexandriaVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Alpharetta, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,625 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,366 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,625 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,366 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,991 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 105 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Alpharetta, GA 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,056 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,425 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,056 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,425 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,481 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 73 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAlpharettaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Arlington, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,998 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 638 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,998 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 638 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,636 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 49 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustArlingtonVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Atlanta, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 296 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 748 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 296 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 748 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,044 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 77 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Atlanta, GA 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 2,130 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,623 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 2,130 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,623 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,753 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 125 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAtlantaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Augusta, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 472 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 443 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 472 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 443 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 915 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 137 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Augusta, GA 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 865 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 872 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 865 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 872 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,737 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 134 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 10 years |  |  |  |
Operating Lease | SunTrust Augusta, GA 3 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 352 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 397 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 352 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 397 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 749 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 122 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAugustaGA3Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Avon Park, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 360 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,564 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 360 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,564 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,924 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 80 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustAvonParkFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Bartow, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 218 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 769 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 218 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 769 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 987 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 47 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBartowFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Beaverdam, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 230 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 309 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 230 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 309 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 539 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 95 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeaverdamVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Belleview, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 226 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,085 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 226 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,085 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,311 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 56 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBelleviewFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Beverly Hills, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 376 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,414 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 376 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,414 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,790 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 73 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBeverlyHillsFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Black Mountain, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 780 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 655 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 780 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 655 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,435 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 202 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBlackMountainNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Bladensburg, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,528 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,538 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,528 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,538 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,066 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 79 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBladensburgMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Boca Raton, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,663 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 654 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,663 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 654 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,317 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 101 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBocaRatonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 10 years |  |  |  |
Operating Lease | SunTrust Bradenton, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 437 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,251 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 429 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,251 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,680 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 64 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBradentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Brunswick, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 158 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,169 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 158 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,169 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,327 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 669 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustBrunswickGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Butner, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 344 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 606 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 344 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 606 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 950 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 47 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustButnerNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Cape Coral, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,065 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,032 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,065 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,032 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,097 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 80 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCapeCoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Cary, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 616 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 826 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 616 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 826 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,442 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 64 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCaryNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Chapel Hill, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 323 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 541 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 323 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 541 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 864 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 56 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChapelHillNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Chattanooga, TN |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 496 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 824 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 496 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 824 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,320 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 254 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Chattanooga, TN 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 308 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 652 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 308 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 652 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 960 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 201 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Chattanooga, TN 3 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 260 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 374 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 260 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 374 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 634 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 115 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN3Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Chattanooga, TN 4 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 336 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 341 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 336 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 341 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 677 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 105 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChattanoogaTN4Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Chestertown, MD |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 856 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 290 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 856 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 290 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,146 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 89 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustChestertownMDMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Clearwater, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 433 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 530 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 433 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 530 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 963 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 54 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustClearwaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Conyers, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 366 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 501 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 366 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 501 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 867 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 77 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustConyersGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 10 years |  |  |  |
Operating Lease | SunTrust Crystal River, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 430 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,971 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 430 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,971 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,401 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 131 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustCrystalRiverFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | SunTrust Dayton Beach Shores, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 318 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 720 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 318 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 720 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,038 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 44 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDaytonBeachShoresFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Deland, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 270 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,296 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 270 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,296 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,566 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 67 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDelandFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Denton, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 472 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 783 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 472 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 783 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,255 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 80 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDentonFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Doral, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,912 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,100 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,912 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,100 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,012 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 85 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDoralFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Douglas, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 354 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 168 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 354 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 168 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 522 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 52 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDouglasGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Duluth, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 851 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 845 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 851 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 845 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,696 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 65 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustDuluthGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Edgewater, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 419 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,417 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 419 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,417 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,836 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 73 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustEdgewaterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Erwin, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 380 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 89 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 380 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 89 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 469 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 27 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustErwinNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Flager Beach, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 366 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,313 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 366 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,313 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,679 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 58 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFlagerBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | SunTrust Fort Myers, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 543 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 758 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 543 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 758 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,301 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 47 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMyersFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Fort Meyers, FL 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 814 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 684 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 814 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 684 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,498 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 70 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFortMeyersFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Franklin, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 103 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 911 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 103 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 911 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,014 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 94 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustFranklinVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Gainesville, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 406 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,830 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 406 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,830 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,236 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 564 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGainesvilleGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Greenacres City, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,395 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,533 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,395 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,533 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,928 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 79 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreenacresCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Greensboro, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 516 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 394 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 516 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 394 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 910 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 121 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGreensboroNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Gulf Breeze, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,021 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,382 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,021 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,382 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,403 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 213 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustGulfBreezeFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 10 years |  |  |  |
Operating Lease | SunTrust Haines City, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 405 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,241 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 405 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,241 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,646 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 64 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHainesCityFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | SunTrust Hallandale Beach, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,735 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,343 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,735 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,343 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,078 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 181 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHallandaleBeachFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Harrisonburg, VA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 245 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 438 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 245 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 438 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 683 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 135 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHarrisonburgVAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Hialeah, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 2,578 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,149 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 2,578 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,149 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,727 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 177 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHialeahFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 10 years |  |  |  |
Operating Lease | SunTrust Holly Hill, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 509 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 699 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 509 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 699 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,208 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 216 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHollyHillFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Homosassa, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 344 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 825 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 344 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 825 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,169 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 51 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHomosassaFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Hudson, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 220 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 207 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 220 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 207 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 427 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 16 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHudsonNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Huntersville, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 177 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 830 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 177 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 830 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,007 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 51 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustHuntersvilleNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Inverness, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 471 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 755 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 471 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 755 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,226 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 78 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustInvernessFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | SunTrust Jacksonville, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 674 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 821 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 674 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 821 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,495 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 51 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | SunTrust Jacksonville, FL 2 |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 938 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 926 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 938 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 926 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,864 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 71 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJacksonvilleFL2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | SunTrust Jonesboro, GA |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 591 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,185 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 591 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,185 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,776 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 365 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroGAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Jonesborough, TN |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 95 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 285 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 95 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 285 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 380 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 88 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJonesboroughTNMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
Operating Lease | SunTrust Jupiter, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 0 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJupiterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,035 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJupiterFLMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,327 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJupiterFLMember |  |  |  |
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Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,327 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJupiterFLMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,362 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustJupiterFLMember | [1],[2] |  |  |
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Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | SunTrust Kannapolis, NC |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
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Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustKannapolisNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 850 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustKannapolisNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 834 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustKannapolisNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,684 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustKannapolisNCMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | $ 257 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_SunTrustKannapolisNCMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 5 years |  |  |  |
[1] | Transactions in real estate and accumulated depreciation during 2014, 2013, and 2012 are summarized as follows: 2014 2013 2012Land, buildings, and leasehold interests: Balance at the beginning of year$4,686,844 $4,145,368 $3,531,845Acquisitions, completed construction and tenant improvements601,168 602,836 701,054Disposition of land, buildings, and leasehold interests(50,938) (57,254) (77,219)Provision for loss on impairment of real estate(823) (4,106) (10,312)Balance at the close of year$5,236,251 $4,686,844 $4,145,368Accumulated depreciation and amortization: Balance at the beginning of year$418,136 $333,778 $270,621Disposition of land, buildings, and leasehold interests(9,153) (6,778) (6,980)Depreciation and amortization expense104,192 91,136 70,137Balance at the close of year$513,175 $418,136 $333,778
[2] | As of December 31, 2014, the leases are treated as either operating or financing leases for federal income tax purposes. As of December 31, 2014, the aggregate cost of the properties owned by NNN that are under operating leases were $5,119,673 and financing leases were $2,703.

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