Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross | $ 163,034us-gaap_FiniteLivedIntangibleAssetsGross | $ 135,120us-gaap_FiniteLivedIntangibleAssetsGross |
Finite-lived intangible assets, accumulated amortization | (53,696)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization | (47,630)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization |
Below market leases, gross | 15,939us-gaap_BelowMarketLeaseGross | 12,672us-gaap_BelowMarketLeaseGross |
Below market leases, accumulated amortization | (7,345)us-gaap_BelowMarketLeaseAccumulatedAmortization | (6,657)us-gaap_BelowMarketLeaseAccumulatedAmortization |
In-Place Leases [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
59,233us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_InPlaceLeasesMember |
47,442us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_InPlaceLeasesMember |
Finite-lived intangible assets, accumulated amortization |
(17,379)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_InPlaceLeasesMember |
(15,158)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_InPlaceLeasesMember |
Leasing Costs [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
38,305us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_LeasingCostsMember |
31,339us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_LeasingCostsMember |
Finite-lived intangible assets, accumulated amortization |
(11,411)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_LeasingCostsMember |
(9,323)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_LeasingCostsMember |
Customer Relationships [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
41,243us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember |
35,739us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember |
Finite-lived intangible assets, accumulated amortization |
(11,177)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember |
(10,407)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember |
Total Lease Intangibles [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
138,781us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_TotalLeaseIntangiblesMember |
114,520us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_TotalLeaseIntangiblesMember |
Finite-lived intangible assets, accumulated amortization |
(39,967)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_TotalLeaseIntangiblesMember |
(34,888)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_TotalLeaseIntangiblesMember |
Above Market Leases [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
8,314us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_AboveMarketLeasesMember |
7,928us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_AboveMarketLeasesMember |
Finite-lived intangible assets, accumulated amortization |
(6,384)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_AboveMarketLeasesMember |
(6,085)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_AboveMarketLeasesMember |
Above and Below Market Leases [Member] | ||
Finite-Lived Intangible Assets [Line Items] | ||
Finite-lived intangible assets, gross |
24,253us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
20,600us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
Finite-lived intangible assets, accumulated amortization |
$ (13,729)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
$ (12,742)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = good_AboveAndBelowMarketLeasesMember |
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- Definition
Amount of accumulated amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life. No definition available.
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Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life. No definition available.
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- Definition
Accumulated amount of 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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- Definition
Amount before 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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