XML 73 R50.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Mortgage Notes Payable and Credit Facility - Mortgage Notes Payable (Details) $ in Thousands |  | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Oct. 27, 2017 | Sep. 30, 2019 | Dec. 31, 2019 USD ($) property mortgage | Dec. 31, 2018 USD ($) property | Dec. 31, 2017 USD ($) | Dec. 27, 2018 property
Debt Instrument [Line Items] |  |  |  |  |  |
Debt repaid |  |  | $ 57,438 | $ 27,850 | $ 60,080 |
Number of properties acquired | property |  |  | 18 | 5 |  |
Weighted Average Interest Rate on Fixed Rate Debt Extended |  |  | 4.18% |  |  |
Variable rate mortgage loans |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt repaid |  |  | $ 13,600 |  |  |
Fixed rate mortgage loans |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt repaid |  |  | $ 31,385 |  |  |
Stated interest rate (as a percent) |  |  | 4.55% |  |  |
New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 69,650 |  |  |
Stated interest rate (as a percent) |  |  | 3.90% |  |  |
LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Weighted Average Interest Rate on Variable Rate Debt Repaid | 2.75% |  |  |  |  |
LIBOR | Variable rate mortgage loans | Weighted Average |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Weighted Average Interest Rate on Variable Rate Debt Repaid |  |  | 2.47% |  |  |
Property Maturing February 8, 2029 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 10,600 |  |  |
Number of properties acquired | property |  |  |  |  |  | 1
Debt instrument term |  | 7 years |  |  |  |
Stated interest rate (as a percent) |  |  | 4.70% |  |  |
Property Maturing February 8, 2029 | LIBOR | Variable rate mortgage loans | Weighted Average |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Weighted Average Interest Rate on Variable Rate Debt Repaid |  | 1.80% |  |  |  |
Property Maturing February 8, 2029 | LIBOR | Fixed rate mortgage loans | Weighted Average |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Weighted Average Interest Rate on Variable Rate Debt Repaid |  | 1.80% |  |  |  |
Property Maturing February 8, 2029 | Treasury Rate | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument term |  |  | 3 years |  |  |
Property Maturing June 1, 2024 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 21,600 |  |  |
Number of properties acquired | property |  |  |  |  |  | 1
Stated interest rate (as a percent) |  |  | 3.42% |  |  |
Property Maturing June 18, 2024 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 8,900 |  |  |
Stated interest rate (as a percent) |  |  | 4.35% |  |  |
Property Maturing December 10, 2026 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 4,800 |  |  |
Stated interest rate (as a percent) |  |  | 3.97% |  |  |
Property Maturing December 17, 2026 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 4,200 |  |  |
Stated interest rate (as a percent) |  |  | 3.97% |  |  |
Property Maturing January 1, 2027 | New fixed rate mortgage notes payable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Fixed Rate Debt Issued |  |  | $ 19,500 |  |  |
Stated interest rate (as a percent) |  |  | 3.75% |  |  |
Mortgages | Variable rate mortgage loans debt extended |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Aggregate Variable Rate Debt Extended |  |  | $ 12,561 |  |  |
Debt instrument term |  |  | 2 years 4 months 10 days |  |  |
Number of Long Term Mortgages Maturities Extended | mortgage |  |  | 2 |  |  |
Number of Properties that Collateralize Mortgage Notes Payable | property |  |  | 4 |  |  |
Mortgages | LIBOR | Variable rate mortgage loans debt extended | Weighted Average |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Weighted Average Interest Rate on Variable Rate Debt Repaid |  |  | 2.51117% |  |  |

X
- Definition Number of properties acquired. + References No definition available. + Details
Name: | good_NumberOfPropertiesAcquired
Namespace Prefix: | good_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Long Term Mortgages Maturities Extended + References No definition available. + Details
Name: | good_NumberofLongTermMortgagesMaturitiesExtended
Namespace Prefix: | good_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Properties that Collateralize Mortgage Notes Payable + References No definition available. + Details
Name: | good_NumberofPropertiesthatCollateralizeMortgageNotesPayable
Namespace Prefix: | good_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
Name: | us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. + References No definition available. + Details
Name: | us-gaap_LongtermDebtPercentageBearingVariableInterestAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 + Details
Name: | us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfSecuredDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=good_VariableRateMortgagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=good_FixedRateMortgageLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=good_NewFixedRateMortgageNotesPayableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingFebruary82029Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_UsTreasuryUstInterestRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingJune12024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingJune182024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingDecember102026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingDecember172026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=good_PropertyMaturingJanuary12027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_MortgagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=good_VariableRateMortgageLoansDebtExtendedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |