Unaudited Condensed Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 46,702	$ (34,226)	$ 10,363	$ (9,475)
Other comprehensive (loss) income:
Foreign currency translation loss	5,736	(4,044)	5,713	(4,647)
Total other comprehensive (loss) income	5,736	(4,044)	5,713	(4,647)
Comprehensive income (loss)	52,438	(38,270)	16,076	(14,122)
Less: comprehensive income attributable to non-controlling interest	976	1,482	3,555	7,017
Comprehensive income (loss) attributable to Iconix Brand Group, Inc.	$ 51,462	$ (39,752)	$ 12,521	$ (21,139)