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

Mortgage Notes Payable, Revolving Credit Facility, and Term Loan Facility Narrative (Detail)

Mortgage Notes Payable, Revolving Credit Facility, and Term Loan Facility Narrative (Detail)		12 Months Ended
	Oct. 27, 2017	Dec. 31, 2017 property mortgage
Debt Instrument [Line Items]
Weighted average interest rate on debt outstanding (as percent)		4.42%
Encumbered properties		96
Revolving Credit Facility
Debt Instrument [Line Items]
Encumbered properties		29
Fixed rate mortgage loans
Debt Instrument [Line Items]
Weighted average interest rate on debt outstanding (as percent)		6.25%
Encumbered properties		48
Mortgage Notes Payable
Debt Instrument [Line Items]
Number of mortgage notes payable \| mortgage		45
Maturity date of mortgage notes payable, start date		Jul. 01, 2018
Maturity date of mortgage notes payable, end date		Jul. 01, 2045
Weighted average interest rate on debt outstanding (as percent)		4.56%
Encumbered properties		67
Variable rate mortgage loans
Debt Instrument [Line Items]
Encumbered properties		19
Variable rate Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Libor rate (as percent)		1.75%
Encumbered properties		29
New Fixed Rate Mortgage Notes Payable
Debt Instrument [Line Items]
Weighted average interest rate on debt outstanding (as percent)		3.78%
Minimum \| Fixed rate mortgage loans
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		3.55%
Minimum \| Variable rate mortgage loans
Debt Instrument [Line Items]
Libor rate (as percent)		2.15%
Maximum \| Fixed rate mortgage loans
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		6.63%
Maximum \| Variable rate mortgage loans
Debt Instrument [Line Items]
Libor rate (as percent)		2.75%
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Libor rate (as percent)	2.75%	1.56%