Reconciliation of Consideration Paid and Estimated Fair Value of Assets Acquired (Detail) - USD ($) $ in Thousands	1 Months Ended					9 Months Ended
	Mar. 31, 2015	Feb. 28, 2015	Feb. 28, 2014	Jan. 31, 2014	Feb. 28, 2013	Sep. 30, 2015		Sep. 30, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Gain on re-measurement of initial equity investment						$ 49,990		$ 28,897
Goodwill						293,849	[1]		$ 232,776
Iconix Latin America
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid			$ 42,000
Fair Value of non-controlling interest			42,698
Book value of Company equity investment prior to 2015 Buy-out			7,950
Gain on re-measurement of initial equity investment			34,748
Business Combination, Reconciliation of Cash Paid and Fair Value of Sellers Non-controlling Interest			85,396
Trademarks			82,400
Cash			1,842
Goodwill			1,130
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total			85,396
Less: note receivable owed to the Company			(1,695)
Add: accrued distributions due to New Brands			997
Working capital deficit			(676)
Iconix Europe
Business Acquisition [Line Items]
Fair Value of non-controlling interest				$ 13,800
Book value of Company equity investment prior to 2015 Buy-out				19,651
Business Combination, Reconciliation of Cash Paid and Fair Value of Sellers Non-controlling Interest				27,600
Trademarks				27,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total				27,600
Working capital deficit				(77)
Loss on re-measurement of initial equity investment				(5,851)
Cash				$ 677
Buffalo Brand
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid					$ 39,614
Fair Value of non-controlling interest					59,489
Trademarks					102,643
Goodwill					7,131
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total					99,103
Deferred tax liability					(14,011)
Licensing contracts | Iconix Latin America
Business Acquisition [Line Items]
Finite intangible assets			$ 700
Licensing contracts | Buffalo Brand
Business Acquisition [Line Items]
Finite intangible assets					2,400
Non-compete agreements | Buffalo Brand
Business Acquisition [Line Items]
Finite intangible assets					$ 940
Pony International, LLC.
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid		$ 37,000
Fair Value of non-controlling interest		12,333
Trademarks		32,381
Goodwill		14,702
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total		49,333
Accounts receivable		2,000
Pony International, LLC. | Licensing contracts
Business Acquisition [Line Items]
Finite intangible assets		$ 250
Iconix China
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	$ 40,400
Fair Value of non-controlling interest	57,372					57,372
Book value of Company equity investment prior to 2015 Buy-out						7,382
Gain on re-measurement of initial equity investment						49,990
Business Combination, Reconciliation of Cash Paid and Fair Value of Sellers Non-controlling Interest						114,744
Trademarks						40,501
Investments in private companies						38,870
Cash						20,184
Other assets						5,997
Accrued expenses						(447)
Goodwill						9,639
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total						$ 114,744
Iconix China | Novel
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	40,400
Shares issued	15,703
Offset of accounts receivable	1,269
Strawberry Shortcake
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	105,000
Trademarks	55,761
Goodwill	35,375
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	95,000
Accounts receivable	3,397
Strawberry Shortcake | American Greetings Corporation
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	95,000
Strawberry Shortcake | Licensing contracts
Business Acquisition [Line Items]
Finite intangible assets	$ 467

[1] Included in the adjustment amounts for goodwill, trademarks and other intangibles, net, investments and joint ventures, other assets – current, and accumulated other comprehensive loss are adjustments of approximately $54.5 million, $(50.8) million, $(4.7) million, $0.1 million and $0.9 milllion, respectively, which were not part of the restatement but are to reflect the final purchase price allocation (which was completed in the fourth quarter of 2015) for the buy-out of the remaining 50% interest in Iconix China as well as the acquisitions of Strawberry Shortcake and PONY and the temporary mark-to-market adjustment associated with the available-for-sale securities acquired as part of the buy-out of the remaining 50% interest in Iconix China. Refer to Note 2 and Note 3 for further details.