Reconciliation of Consideration Paid and Estimated Fair Value of Assets Acquired (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Feb. 28, 2015	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	93,546		93,546
Goodwill	500		500
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	105,000		105,000
Note receivable	8,654		8,654
Licensing agreements | Strawberry Shortcake
Business Acquisition [Line Items]
Finite intangible assets	2,300		2,300
Pony International, LLC.
Business Acquisition [Line Items]
Business acquisition purchase price, cash paid				37,000
Fair Value of non-controlling interest				12,333
Trademarks				47,950
Goodwill	800		800	833
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total				49,333
Pony International, LLC. | Licensing agreements
Business Acquisition [Line Items]
Finite intangible assets				550
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	5,432		5,432
Accrued expenses	(447)		(447)
Goodwill	6,415		6,415
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net, Total	$ 114,743		$ 114,743