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Real Estate and Intangible Assets - Estimated Aggregate Amortization Expense and Net Increase to Rental Income (Detail) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2015
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Dec. 31, 2014
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| Expected Amortization Expense [Line Items] | ||
| Nine Months Ending December 31, 2015 | $ 13,962us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear | |
| 2016 | 13,648us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths | |
| 2017 | 12,167us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo | |
| 2018 | 12,058us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree | |
| 2019 | 12,051us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour | |
| Thereafter | 38,922good_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour | |
| Total | 102,808us-gaap_FiniteLivedIntangibleAssetsNet | 98,814us-gaap_FiniteLivedIntangibleAssetsNet |
| Above and Below Market Leases [Member] | ||
| Expected Amortization Expense [Line Items] | ||
| Nine Months Ending December 31, 2015 |
228good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableRemainderOfFiscalYear / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| 2016 |
307good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableInTwoYears / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| 2017 |
429good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableInThreeYears / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| 2018 |
429good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableInFourYears / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| 2019 |
429good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableInFiveYears / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| Thereafter |
3,754good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivableThereafter / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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| Total |
$ 5,576good_OperatingLeasesEstimatedFutureMinimumPaymentsReceivable / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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- Details
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- Definition
Finite lived intangible assets amortization expense after year four No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, in five years. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, in four years. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, in three years. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, in two years. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, remainder of fiscal year. No definition available.
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- Definition
Operating leases, estimated future minimum payments receivable, thereafter. No definition available.
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- Definition
Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition
Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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