Gladstone Commercial Corporation Annual report pursuant to Section 13 and 15(d)

Schedule III - Real Estate and Accumulated Depreciation - Change in Balance of Accumulated Depreciation (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Balance at beginning of period	$ 81,241	$ 65,730	$ 53,784
Additions during period	18,814	15,511	11,946
Dispositions during period	(7,922)
Balance at end of period	$ 92,133	$ 81,241	$ 65,730