Discontinued Operations - Summary of Financial Results of Entertainment Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other expenses (income):
Income from operations of discontinued operations before income taxes	$ (11,140)	$ 3,387	$ (23,924)	$ 10,625
Gain on sale of Entertainment segment	104,327		104,327
Provision for income taxes	34,060	805	28,962	2,577
Net income from discontinued operations	59,127	2,582	51,441	8,048
Less: Net income attributable to non-controlling interest from discontinued operations	1,634	1,602	2,943	3,081
Net income from discontinued operations attributable to Iconix Brand Group, Inc.	57,493	980	48,498	4,967
Operating Segments | Entertainment
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Licensing revenue	25,669	27,534	53,129	54,490
Selling, general and administrative expenses	16,691	17,632	34,542	36,520
Depreciation and amortization	117	137	303	269
Operating income	8,861	9,765	18,284	17,701
Other expenses (income):
Interest expense	6,548	6,492	12,973	8,183
Interest income	(81)	(176)	(180)	(359)
Loss on extinguishment of debt	13,509		29,246
Foreign currency translation loss (gain)	25	62	169	(748)
Other expenses (income) – net	20,001	6,378	42,208	7,076
Income from operations of discontinued operations before income taxes	(11,140)	3,387	(23,924)	10,625
Gain on sale of Entertainment segment	104,327		104,327
Provision for income taxes	34,060	805	28,962	2,577
Net income from discontinued operations	59,127	2,582	51,441	8,048
Less: Net income attributable to non-controlling interest from discontinued operations	1,634	1,602	2,943	3,081
Net income from discontinued operations attributable to Iconix Brand Group, Inc.	$ 57,493	$ 980	$ 48,498	$ 4,967