Consolidated Statement of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Licensing revenue	$ 187,689	$ 225,833
Type of Revenue [Extensible List]	us-gaap:LicenseMember	us-gaap:LicenseMember
Selling, general and administrative expenses	$ 121,429	$ 114,606
Loss on termination of licenses	10,550	28,360
Depreciation and amortization	2,329	2,455
Equity (earnings) loss on joint ventures	(3,043)	3,259
Gain on deconsolidation of joint venture		(3,772)
Gains on sale of trademarks, net	(1,268)	(875)
Goodwill impairment	37,812	103,877
Trademark impairment	136,417	525,726
Investment impairment	2,500	16,848
Operating loss	(119,037)	(564,651)
Other expenses (income):
Interest expense	59,214	67,901
Interest income	(495)	(480)
Other income, net	(91,305)	(2,650)
(Gain) loss on extinguishment of debt	(4,473)	20,939
Foreign currency translation loss	1,153	3,071
Other expenses (income) – net	(35,906)	88,781
Loss from continuing operations before income taxes	(83,131)	(653,432)
Provision (benefit) for income taxes	6,538	(95,977)
Net loss from continuing operations	(89,669)	(557,455)
Less: Net gain (loss) attributable to non-controlling interest from continuing operations	10,852	(22,177)
Net loss from continuing operations attributable to Iconix Brand Group, Inc.	(100,521)	(535,278)
Loss from discontinued operations before income taxes		(26,232)
Gain on sale of Entertainment segment		104,099
Provision for income taxes		28,899
Net income from discontinued operations		48,968
Less: Net income attributable to non-controlling interest from discontinued operations		2,943
Net income from discontinued operations attributable to Iconix Brand Group, Inc.		46,025
Net loss attributable to Iconix Brand Group, Inc.	$ (100,521)	$ (489,253)
(Loss) earnings per share - basic:
Continuing operations	$ (15.73)	$ (94.71)
Discontinued operations		8.06
(Loss) earnings per share - basic:	(15.73)	(86.65)
(Loss) earnings per share - diluted:
Continuing operations	(15.73)	(94.71)
Discontinued operations		8.06
(Loss) earnings per share - diluted	$ (15.73)	$ (86.65)
Weighted average number of common shares outstanding:
Basic	6,734	5,711
Diluted	6,734	5,711