Consolidated Statement of Operations - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Licensing revenue	$ 148,984,000	$ 187,689,000
Type of Revenue [Extensible List]	us-gaap:LicenseMember	us-gaap:LicenseMember
Selling, general and administrative expenses	$ 83,996,000	$ 121,429,000
Loss on termination of licenses		10,550,000
Depreciation and amortization	1,816,000	2,329,000
Equity (earnings) loss on joint ventures	(14,000)	(3,043,000)
Gains on sale of trademarks, net		(1,268,000)
Asset impairment	1,766,000
Goodwill impairment	0	37,812,000
Trademark impairment	65,587,000	136,417,000
Investment impairment	26,613,000	2,500,000
Operating income (loss)	(30,780,000)	(119,037,000)
Other expenses (income):
Interest expense	57,264,000	59,214,000
Interest income	(360,000)	(495,000)
Other (income) loss, net	5,291,000	(91,305,000)
Gain on extinguishment of debt		(4,473,000)
Foreign currency translation loss	858,000	1,153,000
Other expenses (income) – net	63,053,000	(35,906,000)
Income (loss) before income taxes	(93,833,000)	(83,131,000)
Provision for income taxes	8,083,000	6,538,000
Net loss	(101,916,000)	(89,669,000)
Less: Net income attributable to non-controlling interest	9,597,000	10,852,000
Net loss attributable to Iconix Brand Group, Inc.	$ (111,513,000)	$ (100,521,000)
Earnings (loss) per share:
Basic	$ (10.56)	$ (14.93)
Diluted	$ (10.56)	$ (14.93)
Weighted average number of common shares outstanding:
Basic	10,559	6,734
Diluted	10,559	6,734