XML 36 R25.htm IDEA: XBRL DOCUMENT
v3.20.2

Accounting Policies - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Jan. 01, 2020 | Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Investment in direct financing leases, net | $ 79,767,000 |  | $ 79,767,000 |  |  | $ 82,366,000
Impairments | 507,000 | $ 701,000 | 1,538,000 | $ 1,472,000 |  |
Notes and mortgages receivable | $ 29,675,000 |  | $ 29,675,000 |  |  | $ 30,855,000
Level 3 [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Assumed annual average rent increases for unobservable inputs |  |  | 2.00% |  |  |
Level 3 [Member] | Measurement Input Expected Term [Member] | Maximum [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Assumed holding periods for unobservable inputs |  |  | 15 years |  |  |
Level 3 [Member] | Measurement Input Cap Rate [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Real estate fair value, measurement input | 8.00% |  | 8.00% |  |  |
Level 3 [Member] | Measurement Input Discount Rate [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Real estate fair value, measurement input | 7.00% |  | 7.00% |  |  |
Properties [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments |  |  | $ 306,000 | 362,000 |  |
Estimated Sale Price Method [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments |  |  | 260,000 |  |  |
Discounted Cash Flow Method [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments |  |  | 117,000 |  |  |
Accumulation of Asset Retirement Cost Method [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments |  |  | 1,161,000 |  |  |
Notes and Mortgages Receivable [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments | $ 0 | 0 | 0 | 0 |  |
Direct Financing Leases Financing Receivable [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Impairments | 0 | $ 0 | 0 | $ 0 |  |
Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Investment in direct financing leases, net |  |  |  |  | $ 82,366,000 |
Estimated credit loss reserve related to direct financing leases |  |  |  |  | 578,000 |
Credit loss reserve |  |  |  |  | 309,000 |
Notes and mortgages receivable |  |  |  |  | $ 30,855,000 |
Accounting Standards Update 2016-13 [Member] | Notes and Mortgages Receivable [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Additional allowance for credit losses | 0 |  | 0 |  |  |
Accounting Standards Update 2016-13 [Member] | Construction Loans [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Notes and mortgages receivable | 2,200,000 |  | 2,200,000 |  |  |
Accounting Standards Update 2016-13 [Member] | Direct Financing Leases Financing Receivable [Member] |  |  |  |  |  |
Organization Consolidation And Presentation Of Financial Statements [Line Items] |  |  |  |  |  |
Additional allowance for credit losses | $ 0 |  | $ 0 |  |  |

X
- Definition Credit loss reserve. + References No definition available. + Details
Name: | gty_CreditLossReserve
Namespace Prefix: | gty_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Estimated credit loss reserve related to direct financing leases. + References No definition available. + Details
Name: | gty_EstimatedCreditLossReserveRelatedToDirectFinancingLeases
Namespace Prefix: | gty_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Value of input used to measure long lived assets. + References No definition available. + Details
Name: | gty_LongLivedAssetsMeasurementInput
Namespace Prefix: | gty_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Notes and mortgages receivable. + References No definition available. + Details
Name: | gty_NotesAndMortgagesReceivable
Namespace Prefix: | gty_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Organization consolidation and presentation of financial statements. + References No definition available. + Details
Name: | gty_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems
Namespace Prefix: | gty_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage of annual assumed average rent increases used as an unobservable input to measure the fair value. + References No definition available. + Details
Name: | gty_PercentageAnnualAssumedAverageRentIncreasesUnobservableInputs
Namespace Prefix: | gty_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Property plant and equipment assumed holding periods. + References No definition available. + Details
Name: | gty_PropertyPlantAndEquipmentAssumedHoldingPeriods
Namespace Prefix: | gty_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
Name: | us-gaap_AssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The net investment in direct financing leases as of the balance sheet date consisting of: (a) minimum lease payments due on direct financing leases, (b) unguaranteed residual value, and (c) any unamortized initial direct costs; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121568338&loc=d3e45377-112738 + Details
Name: | us-gaap_CapitalLeasesNetInvestmentInDirectFinancingLeases
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputExpectedTermMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputCapRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_PropertyPlantAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis=gty_EstimatedSalePriceMethodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis=gty_DiscountedCashFlowMethodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis=gty_AccumulationOfAssetRetirementCostMethodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=gty_NotesAndMortgagesReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_FinanceLeasesPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201613Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |