Rate Reconciliation Between Amount of Income Tax Provision (Benefit) at Federal Rate and Provision (Benefit) from Taxes on Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2015	[1]	Sep. 30, 2015	[1]	Jun. 30, 2015	[1]	Mar. 31, 2015	[1]	Dec. 31, 2014	[2]	Sep. 30, 2014	[2]	Jun. 30, 2014	[2]	Mar. 31, 2014	[2]	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Income tax provision (benefit) computed at the federal rate of 35%																	$ (99,496)	$ 58,489	$ 58,410
Increase (reduction) in income taxes resulting from:
State and local income taxes (benefit), net of federal income tax																	6,337	3,090	991
Non-controlling interest																	(938)	(6,552)	(5,809)
Unrecognized tax benefits																	6,985
Valuation allowance																	(11,205)
Non-deductible executive compensation																	645	1,018	727
Foreign Earnings (rate differential)																	349	(8,472)	(4,998)
Other, net																	1,979	715	274
Provision (benefit) for income taxes	$ (140,427)		$ 6,275		$ 11,536		$ 27,272		$ 5,210		$ 8,867		$ 14,213		$ 19,998		$ (95,344)	$ 48,288	$ 49,595

[1] FY 2015: Operating income (loss), net includes a non-cash impairment charge of $437.5 million primarily related to the men’s brands recorded in the fourth quarter. Included in net income (loss) attributable to Iconix Brand Group, Inc. is a non-cash pre-tax re-measurement gain of approximately $50.0 million related to the purchase of the remaining interest in Iconix China in the first quarter.

[2] FY 2014 (Restated): Operating income, net includes a net gain of $6.4 million on the sale of the “sharperimage.com” domain name and certain categories under the Sharper Image trademark in the second quarter. Included in net income attributable to Iconix Brand Group, Inc is a non-cash pre-tax re-measurement gain of approximately $34.7 million related to the purchase of the remaining interest in Iconix Latin America in the first quarter.