Consolidated Statement of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Licensing revenue	$ 225,833	$ 255,143	$ 271,590
Selling, general and administrative expenses	114,606	128,759	134,006
Loss on termination of licenses	28,360
Depreciation and amortization	2,455	2,793	4,317
Equity loss (earnings) on joint ventures	3,259	(3,578)	(5,330)
Gain on deconsolidation of joint venture	(3,772)
Gains on sale of trademarks, net	(875)	(38,104)
Goodwill impairment	103,877	18,331	35,132
Trademark impairment	525,726	419,762	402,392
Investment impairment	16,848
Operating loss	(564,651)	(272,820)	(298,927)
Other expenses (income):
Interest expense	67,901	76,925	79,427
Interest income	(480)	(904)	(3,375)
Other income, net	(2,650)	(17,508)	(50,904)
Loss on extinguishment of debt, net	20,939	5,903
Foreign currency translation loss (gain)	3,071	(1,287)	(10,076)
Other expenses – net	88,781	63,129	15,072
Loss from continuing operations before income taxes	(653,432)	(335,949)	(313,999)
Benefit for income taxes	(95,977)	(78,125)	(103,901)
Net loss from continuing operations	(557,455)	(257,824)	(210,098)
Less: Net loss attributable to non-controlling interest from continuing operations	(22,177)	(3,326)	(8,439)
Net loss from continuing operations attributable to Iconix Brand Group, Inc.	(535,278)	(254,498)	(201,659)
(Loss) income from discontinued operations before income taxes	(26,232)	9,947	29,725
Gain on sale of Entertainment segment	104,099
Provision for income taxes	28,899	1,631	8,557
Net income from discontinued operations	48,968	8,316	21,168
Less: Net income attributable to non-controlling interest from discontinued operations	2,943	5,952	6,023
Net income from discontinued operations attributable to Iconix Brand Group, Inc.	46,025	2,364	15,145
Net loss attributable to Iconix Brand Group, Inc.	$ (489,253)	$ (252,134)	$ (186,514)
(Loss) earnings per share - basic:
Continuing operations	$ (9.47)	$ (4.86)	$ (4.18)
Discontinued operations	0.81	0.05	0.31
(Loss) earnings per share - basic:	(8.66)	(4.82)	(3.86)
(Loss) earnings per share - diluted:
Continuing operations	(9.47)	(4.86)	(4.18)
Discontinued operations	0.81	0.05	0.31
(Loss) earnings per share - diluted	$ (8.66)	$ (4.82)	$ (3.86)
Weighted average number of common shares outstanding:
Basic	57,112	52,338	48,293
Diluted	57,112	52,338	48,293