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

Real Estate and Intangible Assets - Concentrations (Narrative) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) farm tenant region	Dec. 31, 2016 USD ($) farm	Dec. 31, 2015 USD ($)
Real Estate Properties [Line Items]
Number of tenants \| tenant	52
Number of farms \| farm	73	58
Rental revenue \| $	$ 25,111	$ 17,306	$ 11,888
Total rental revenue (as percent)	100.00%	100.00%
California
Real Estate Properties [Line Items]
Number of farms \| farm	28	22
Rental revenue \| $	$ 12,000	$ 9,829
Total rental revenue (as percent)	47.80%	56.80%
Number of regions farms are located \| region	4
Florida
Real Estate Properties [Line Items]
Number of farms \| farm	16	15
Rental revenue \| $	$ 6,600	$ 3,293
Total rental revenue (as percent)	26.20%	19.00%
Colorado
Real Estate Properties [Line Items]
Number of farms \| farm	10	9
Rental revenue \| $	$ 2,700	$ 1,453
Total rental revenue (as percent)	10.80%	8.40%
Tenant A
Real Estate Properties [Line Items]
Number of farms \| farm	5
Rental revenue \| $	$ 4,300
Total rental revenue (as percent)	17.30%
Dole Food Company
Real Estate Properties [Line Items]
Number of farms \| farm	2
Rental revenue \| $	$ 3,000
Total rental revenue (as percent)	11.80%