Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Licensing revenue	$ 24,462	$ 35,471	$ 74,688	$ 105,806
Type of Revenue [Extensible List]	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember
Selling, general and administrative expenses	$ 9,915	$ 26,318	$ 42,043	$ 60,846
Depreciation and amortization	315	421	894	1,393
Equity (earnings) loss on joint ventures	27	(153)	1,455	(2,290)
Gain on sale of investment			(1,600)
Gain on sale of trademarks	(74,105)		(74,105)
Investment impairment	17,145	17,000	17,245	17,000
Trademark impairment	4,814		23,709
Operating income (loss)	66,351	(8,115)	65,047	28,857
Other expenses (income):
Interest expense	18,489	14,430	52,249	43,399
Interest (income)	(1)	(96)	(51)	(259)
Other (income) loss, net	(285)	11,971	1,851	(6,821)
Foreign currency translation loss	531	391	596	760
Other expenses – net	18,734	26,696	54,645	37,079
Income (loss) before income taxes	47,617	(34,811)	10,402	(8,222)
Provision (Benefit) for income taxes	915	(585)	39	1,253
Net income (loss)	46,702	(34,226)	10,363	(9,475)
Less: Net income attributable to non-controlling interest	976	1,482	3,555	7,017
Net income (loss) attributable to Iconix Brand Group, Inc.	$ 45,726	$ (35,708)	$ 6,808	$ (16,492)
Earnings (loss) per share:
Basic	$ 3.66	$ (3.07)	$ 0.55	$ (1.62)
Diluted	$ 1.51	$ (3.07)	$ 0.37	$ (1.62)
Weighted average number of common shares outstanding:
Basic	12,517	11,631	12,051	10,169
Diluted	31,189	11,631	33,801	10,169