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Increase (decrease) in royalty revenue.

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Percentage of net asset value.

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Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) of the credit facility.

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Basis of Presentation - Additional Information (Detail) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 27, 2017	Jul. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2018	Mar. 15, 2018	Mar. 18, 2013	May 23, 2011
Basis Of Presentation [Line Items]
Loss on termination of licenses			$ 2,750,000		$ 25,980,000
Impairment of intangible assets, indefinite-lived			521,653,000		521,653,000
Non-cash goodwill impairment charge			$ 103,877,000		$ 103,877,000	$ 0
Deutsche Bank \| Subsequent Event \| Maximum
Basis Of Presentation [Line Items]
Aggregate amount of term loan facility	$ 165,700,000
Senior Secured Term Loan Due 2022 \| Deutsche Bank \| Subsequent Event
Basis Of Presentation [Line Items]
Reduction in size of credit facility	(75,000,000)
Aggregate amount of term loan facility	225,000,000
Senior Secured Term Loan Due 2022 \| Deutsche Bank \| Subsequent Event \| Minimum
Basis Of Presentation [Line Items]
Net cash proceeds	100,000,000
Convertible Notes \| Deutsche Bank
Basis Of Presentation [Line Items]
Debt instrument, interest rate, stated percentage			1.50%		1.50%
Convertible Notes \| 1.50% Senior Subordinated Notes Due March 15, 2018
Basis Of Presentation [Line Items]
Debt instrument, interest rate, stated percentage			1.50%	1.50%	1.50%	1.50%			1.50%	2.50%
Debt instrument, Maturity Date			2018-03
Proceeds from escrow account to repay convertible notes			$ 59,000,000
Convertible Notes \| 1.50% Senior Subordinated Notes Due March 15, 2018 \| Deutsche Bank
Basis Of Presentation [Line Items]
Debt instrument, interest rate, stated percentage			1.50%		1.50%
First Delayed Draw Term Loan \| Deutsche Bank \| Subsequent Event
Basis Of Presentation [Line Items]
Aggregate amount of term loan facility	$ 25,000,000
Indefinite-lived trademarks
Basis Of Presentation [Line Items]
Impairment of intangible assets, indefinite-lived			$ 521,700,000
Men's
Basis Of Presentation [Line Items]
Non-cash goodwill impairment charge			1,500,000	$ 18,300,000
Men's \| Indefinite-lived trademarks
Basis Of Presentation [Line Items]
Impairment of intangible assets, indefinite-lived			135,900,000
Women's
Basis Of Presentation [Line Items]
Non-cash goodwill impairment charge			73,900,000	0
Women's \| Indefinite-lived trademarks
Basis Of Presentation [Line Items]
Impairment of intangible assets, indefinite-lived			227,600,000
Home
Basis Of Presentation [Line Items]
Non-cash goodwill impairment charge			28,400,000	$ 0
Home \| Indefinite-lived trademarks
Basis Of Presentation [Line Items]
Impairment of intangible assets, indefinite-lived			69,500,000
International \| Indefinite-lived trademarks
Basis Of Presentation [Line Items]
Impairment of intangible assets, indefinite-lived			$ 88,800,000
Scenario, Forecast \| Second Delayed Draw Term Loan \| Deutsche Bank
Basis Of Presentation [Line Items]
Aggregate amount of term loan facility								$ 140,700,000
Walmart \| Ocean Pacific ("OP") Direct-to-retail ("DTR") License Agreement
Basis Of Presentation [Line Items]
License agreement expiration date					2017-06
Walmart \| Starter DTR License Agreement
Basis Of Presentation [Line Items]
License agreement expiration date					2017-12
Walmart \| DanskinNow License Agreement
Basis Of Presentation [Line Items]
License agreement expiration date					2019-01
Walmart \| DanskinNow License Agreement \| Scenario, Forecast
Basis Of Presentation [Line Items]
Estimated decline of royalty revenue in 2018							$ 15,500,000
Target \| Mossimo DTR License Agreement
Basis Of Presentation [Line Items]
License agreement expiration date					2018-10
Target \| Mossimo DTR License Agreement \| Scenario, Forecast
Basis Of Presentation [Line Items]
Estimated decline of royalty revenue in 2018							$ 10,000,000
Target \| Mossimo License Agreement
Basis Of Presentation [Line Items]
License agreement expiration date					2018-10
Iconix Canada Joint Venture
Basis Of Presentation [Line Items]
Percentage of purchase of ownership interest		50.00%
Purchase of ownership interest		$ 19,000,000
Percentage of net asset value		50.00%
Estimated payments to acquire ownership interest		$ 2,000,000