Reconciliation of Consideration Paid and Estimated Fair Value of Assets Acquired (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Mar. 31, 2015	Feb. 28, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Gain on re-measurement of initial equity investment			$ 47,365	$ 37,893
Goodwill	$ 239,198		239,198		$ 231,738
Strawberry Shortcake
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	105,000
Trademarks	91,007		91,007
Goodwill	500		500
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	105,000		105,000
Note receivable	9,470		9,470
Accounts Receivable	3,223		3,223
Licensing agreements | Strawberry Shortcake
Business Acquisition [Line Items]
Finite intangible assets	800		800
Pony International, LLC.
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid		$ 37,000
Fair Value of non-controlling interest		12,333
Trademarks		46,750
Goodwill	300	333	300
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total		49,333
Accounts Receivable		2,000
Pony International, LLC. | Licensing agreements
Business Acquisition [Line Items]
Finite intangible assets		$ 250
Iconix China
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid	40,400
Shares issued to the seller	15,703		15,703
Offset of accounts receivable	1,269		1,269
Fair Value of non-controlling interest	57,372		57,372
Value of Company equity investment prior to 2015 Buy-out	10,006
Gain on re-measurement of initial equity investment	47,365
Business Combination, Reconciliation of Cash Paid and Fair Value of Sellers Non-controlling Interest	114,743
Trademarks	40,500		40,500
Investments in private companies	42,659		42,659
Cash	20,184		20,184
Other assets	5,997		5,997
Accrued expenses	(447)		(447)
Goodwill	5,850		5,850
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	$ 114,743		$ 114,743