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Schedule III - Real Estate and Accumulated Depreciation and Amortization Under Operating Leases - Table 12 (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 | Health Source Chiropractic Houston, TX |  |  |  |  |
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_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 112 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 509 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 302 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 112 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 811 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 923 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 134 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthSourceChiropracticHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Healthy Pet Suwanee, 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_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 175 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,038 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 175 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,038 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,213 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 209 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetSuwaneeGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Healthy Pet Colonial Heights, 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_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 160 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 746 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 160 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 746 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 906 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 148 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HealthyPetColonialHeightsVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hear USA Lapeer, MI |  |  |  |  |
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_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 29 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 211 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 29 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 201 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 230 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 38 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HearUsaLapeerMiMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hibbett Sports Sealy, TX |  |  |  |  |
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_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 208 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 230 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 208 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 230 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 438 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 95 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HibbettSportsSealyTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hog Pit Tucson, AZ |  |  |  |  |
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_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 827 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 305 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 18 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 845 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 305 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,150 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 114 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HogPitTucsonAzMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hollywood Feed Ridgeland, MS |  |  |  |  |
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_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 343 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 411 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 362 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 343 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 773 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,116 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 135 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HollywoodFeedRidgelandMsMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Home Decor Memphis, 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_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 549 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 540 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 364 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 549 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 904 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,453 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 341 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDecorMemphisTnMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Home Depot Sunrise, 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_HomeDepotSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 5,149 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 5,149 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 5,149 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeDepotSunriseFlMember | [1],[2] |  |  |
Operating Lease | Home Zone Furniture Arlington, TX |  |  |  |  |
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_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 435 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,300 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 334 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 435 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,634 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,069 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 653 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeZoneFurnitureArlingtonTXMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 38 years |  |  |  |
Operating Lease | HomeGoods Fairfax, 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_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 523 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 756 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 1,585 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 971 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,341 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,312 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 811 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HomeGoodsFairfaxVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hometown Urgent Care Warren, OH |  |  |  |  |
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_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 562 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 468 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 100 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 562 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 568 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,130 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 162 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HometownUrgentCareWarrenOhMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hooters Tampa, 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_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 784 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 505 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 784 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 505 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,289 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 165 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HootersTampaFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Humana Sunrise, 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_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 800 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 253 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 800 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 253 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,053 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 67 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HumanaSunriseFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hurrican Grill and Wings Chandler, AZ |  |  |  |  |
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_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 655 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 791 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 57 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 655 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 849 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,504 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 254 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HurricanGrillandWingsChandlerAZMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Hy-Vee St. Joseph, 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_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,580 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,849 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,580 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,849 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,429 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 876 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_HyVeeStJosephMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Insurance Auto Auctions New Orleans, LA |  |  |  |  |
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_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,445 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 4,123 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,445 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 3,987 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 5,432 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 172 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsNewOrleansLAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Insurance Auto Auctions E Dundee, IL |  |  |  |  |
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_InsuranceAutoAuctionsEDundeeILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 2,772 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 2,772 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,772 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_InsuranceAutoAuctionsEDundeeILMember | [1],[2] |  |  |
Operating Lease | Int'l House of Pancakes Midwest City, OK |  |  |  |  |
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_IntlHouseOfPancakesMidwestCityOkMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 407 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesMidwestCityOkMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesMidwestCityOkMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesMidwestCityOkMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesMidwestCityOkMember |  |  |  |
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_IntlHouseOfPancakesMidwestCityOkMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 407 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesMidwestCityOkMember | [1],[2] |  |  |
Operating Lease | Int'l House of Pancakes Ankeny, IA |  |  |  |  |
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_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 693 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 515 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 693 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 515 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember | [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_IntlHouseOfPancakesAnkenyIaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 164 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IntlHouseOfPancakesAnkenyIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | ISD Renal Corpus Christi, TX |  |  |  |  |
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_IsdRenalCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 406 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 4,036 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember |  |  |  |
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_IsdRenalCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 4,036 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,442 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 409 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | ISD Renal Kendallville, IN |  |  |  |  |
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_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 66 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 2,748 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 66 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 2,748 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,814 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 239 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalKendallvilleInMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | ISD Renal Memphis, TN 1 |  |  |  |  |
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_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 180 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 3,223 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 180 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 3,223 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,403 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 327 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn1Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | ISD Renal Memphis, 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_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 283 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 4,146 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 283 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 4,146 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 4,429 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 420 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_IsdRenalMemphisTn2Member |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | J & J Insurance Hollywood, 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_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 195 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 44 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 18 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 119 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 119 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 0 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JAndJInsuranceHollywoodFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 15 years |  |  |  |
Operating Lease | Jack in the Box Plano, TX |  |  |  |  |
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_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,055 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,237 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,055 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,237 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,292 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 295 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JackInBoxPlanoTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jacobson Industrial Des Moines, IA |  |  |  |  |
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_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 61 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 112 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 61 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 112 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 173 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 54 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JacobsonIndustrialDesMoinesIaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | Jared Jewelers Richmond, 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_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 955 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,336 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 955 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,336 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,291 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 436 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersRichmondVaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jared Jewelers Brandon, 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_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,197 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,182 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,197 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,182 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,379 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 374 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersBrandonFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jared Jewelers Lithonia, 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_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,271 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,216 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,271 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,216 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,487 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 384 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersLithoniaGaMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jared Jewelers Houston, TX |  |  |  |  |
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_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,676 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,440 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,676 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,440 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 3,116 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 433 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersHoustonTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jared Jewelers Oviedo, 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_JaredJewelersOviedoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,328 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 0 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,328 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,328 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JaredJewelersOviedoFlMember | [1],[2] |  |  |
Operating Lease | Jazzercise Fitness Center Orlando, FL |  |  |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Real Estate and Accumulated Depreciation, Encumbrances | 17 us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember | [3] |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 37 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 101 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 37 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 101 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 138 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 28 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JazzerciseFitnessCenterOrlandoFlMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jiffy Lube - Auburn, MA |  |  |  |  |
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_JiffyLubeAuburnMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 455 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 856 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember |  |  |  |
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_JiffyLubeAuburnMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 856 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember | [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_JiffyLubeAuburnMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 11 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAuburnMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | Jiffy Lube - Ayer, MA |  |  |  |  |
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_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 326 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 792 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 326 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 792 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,118 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 12 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeAyerMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Jiffy Lube - Barrington, IL |  |  |  |  |
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_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 371 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 612 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 371 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 612 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 983 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 9 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBarringtonILMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Jiffy Lube - Berwyn, IL |  |  |  |  |
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_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 359 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 709 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 359 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 709 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,068 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 9 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBerwynILMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | Jiffy Lube - Bolingbrook, IL |  |  |  |  |
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_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 185 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 562 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 185 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 562 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 747 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 9 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBolingbrookILMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Jiffy Lube - Burbank, IL |  |  |  |  |
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_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 156 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 418 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 156 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 418 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 574 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 10 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeBurbankILMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 20 years |  |  |  |
Operating Lease | Jiffy Lube - Plattsburgh, NY |  |  |  |  |
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_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 127 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 421 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 127 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 421 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 548 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 8 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubePlattsburghNYMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 25 years |  |  |  |
Operating Lease | Jiffy Lube - Romeoville, IL |  |  |  |  |
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_JiffyLubeRomeovilleILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 158 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 557 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember |  |  |  |
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_JiffyLubeRomeovilleILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 557 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 715 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 9 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeRomeovilleILMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 30 years |  |  |  |
Operating Lease | Jiffy Lube - Worcester, MA |  |  |  |  |
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_JiffyLubeWorcesterMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 287 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 827 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember |  |  |  |
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_JiffyLubeWorcesterMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 827 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,114 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 11 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JiffyLubeWorcesterMAMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 35 years |  |  |  |
Operating Lease | Jin's Asian Cafe Sealy, TX |  |  |  |  |
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_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 67 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 74 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 67 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 74 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 141 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 30 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JinsAsianCafeSealyTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jo-Ann etc Corpus Christi, TX |  |  |  |  |
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_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 818 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 896 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 12 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 818 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 909 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 1,727 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 479 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcCorpusChristiTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Jo-Ann etc St Peters, 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_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,741 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 5,406 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 1,233 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,741 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 6,639 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 8,380 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | 1,417 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JoAnnEtcStPetersMoMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 years |  |  |  |
Operating Lease | Johnny Carino's Lubbock, TX |  |  |  |  |
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_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Land | 1,007 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Initial Cost to Company, Building, Improvements & Leasehold Interests | 1,206 us-gaap_RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Improvements | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs | 0 us-gaap_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land | 1,007 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfLand / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Building, Improvements & Leasehold Interests | 1,206 us-gaap_RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Gross Amount at Which Carried at Close of Period, Land, Building, Improvements & Leasehold Interests | 2,213 us-gaap_RealEstateGrossAtCarryingValue / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember | [1],[2] |  |  |
Real Estate and Accumulated Depreciation, Accumulated Depreciation and Amortization | $ 393 us-gaap_RealEstateAccumulatedDepreciation / nnn_ClassificationOfInvestmentPropertyLeasesByTypeOfLeaseAxis = nnn_OperatingLeaseMember / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = nnn_JohnnyCarinosLubbockTxMember |  |  |  |
Real Estate and Accumulated Depreciation, Life on Which Depreciation & Amortization in Latest Income Statement is Computed | 40 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.
[3] | Property is encumbered as a part of NNN's $6,952 long-term, fixed rate mortgage and security agreement.

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