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Changes in Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Goodwill [Line Items]
Net goodwill			$ 63,882
Impairment		$ (103,877)	(37,812)	$ (103,877)
Net goodwill			26,099
Iconix Australia
Goodwill [Line Items]
Acquisition of 5% interest in Iconix Australia			29
Women's
Goodwill [Line Items]
Net goodwill			37,812
Impairment	$ (37,800)		(37,812)
International
Goodwill [Line Items]
Net goodwill			26,070
Net goodwill			26,099
International \| Iconix Australia
Goodwill [Line Items]
Acquisition of 5% interest in Iconix Australia			$ 29