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

Real Estate and Intangible Assets - Weighted Average Amortization Period for Intangible Assets Acquired and Liabilities Assumed (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities	10 years 6 months	13 years 3 months 18 days
In-Place Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities	9 years 1 month 6 days	11 years 10 months 24 days
Leasing Costs [Member]
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities	9 years 1 month 6 days	11 years 10 months 24 days
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities	14 years 1 month 6 days	16 years 10 months 24 days
Above Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities	9 years 8 months 12 days
Below Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Period for intangible assets and liabilities		11 years 10 months 24 days