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

Borrowings - Farmer Mac Facility (Narrative) (Detail)	12 Months Ended
Borrowings - Farmer Mac Facility (Narrative) (Detail)	Dec. 31, 2017 USD ($) farm debt_instrument	Dec. 31, 2016 farm	Jan. 12, 2017 USD ($)	Jun. 16, 2016 USD ($)	Dec. 05, 2014 USD ($)
Debt Instrument [Line Items]
Number of debt instruments issued \| debt_instrument	14
Debt issuance costs, gross	$ 306,000
Number of farms \| farm	73	58
Farmer Mac Bonds Payable
Debt Instrument [Line Items]
Debt instrument, face amount	$ 125,000,000			$ 125,000,000	$ 75,000,000
Debt instrument, extension period	2 years
Debt Instrument, loans to value ratios percentage	60.00%
Number of debt instruments issued \| debt_instrument	14
Aggregate principal amount of outstanding bonds percentage	110.00%
Debt issuance costs, gross	$ 506,000
Number of farms \| farm	13
Book value of collateralized asset	$ 139,800,000
Farmer Mac Bonds Payable Issued in Current Period
Debt Instrument [Line Items]
Debt instrument, face amount			$ 35,625,000
Number of debt instruments issued \| debt_instrument	5
Farm Credit Mortgage Notes Payable
Debt Instrument [Line Items]
Debt instrument, face amount	$ 35,600,000