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

Subsequent Events - Additional Information (Details) $ in Thousands			1 Months Ended	3 Months Ended
	Apr. 30, 2019 USD ($) ft² tenant	Apr. 05, 2019 USD ($) ft² tenant	Apr. 30, 2019 USD ($) ft² shares	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)
Subsequent Event [Line Items]
Purchase price				$ 6,315	$ 14,341
Common Stock \| Subsequent event
Subsequent Event [Line Items]
Number of shares issued (in shares) \| shares			332,709
Series A and B Preferred Stock \| Subsequent event
Subsequent Event [Line Items]
Number of shares issued (in shares) \| shares			0
Orlando, Florida \| Subsequent event
Subsequent Event [Line Items]
Square Footage \| ft²		383,000
Purchase price		$ 19,200
Number of tenants \| tenant		1
Lease Term		20 years
Annualized GAAP Rent		$ 1,500
Columbus, Ohio \| Subsequent event
Subsequent Event [Line Items]
Square Footage \| ft²	54,430		54,430
Purchase price	$ 3,100
Number of tenants \| tenant	1
Lease Term	7 years
Annualized GAAP Rent	$ 200
Common Stock ATM Program \| Common Stock \| Subsequent event
Subsequent Event [Line Items]
Consideration received			$ 6,800