Gladstone Commercial Corporation Quarterly report pursuant to Section 13 or 15(d)

Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail)

Real Estate and Intangible Assets - Carrying Value of Intangible Assets and Accumulated Amortization (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 170,333	$ 163,034
Finite-lived intangible assets, accumulated amortization	(56,353)	(53,696)
Below market leases, gross	15,938us-gaap_BelowMarketLeaseGross	15,939us-gaap_BelowMarketLeaseGross
Below market leases, accumulated amortization	(7,564)	(7,345)
In-Place Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	61,622	59,233
Finite-lived intangible assets, accumulated amortization	(18,583)	(17,379)
Leasing Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	40,361	38,305
Finite-lived intangible assets, accumulated amortization	(12,119)	(11,411)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	43,518	41,243
Finite-lived intangible assets, accumulated amortization	(11,991)	(11,177)
Lease Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	145,501	138,781
Finite-lived intangible assets, accumulated amortization	(42,693)	(39,967)
Above and Below Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	24,832	24,253
Finite-lived intangible assets, accumulated amortization	(13,660)	(13,729)
Above Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	8,894	8,314
Finite-lived intangible assets, accumulated amortization	$ (6,096)	$ (6,384)