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Joint Ventures and Investments - Additional information (Detail) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 31, 2018	Sep. 30, 2018	Sep. 30, 2018
Schedule Of Investments [Line Items]
Revenue reorganized from accrued assets		$ 400,000	$ 400,000
Net income attributable to noncontrolling interest		200,000	200,000
Maximum
Schedule Of Investments [Line Items]
Selling general and administrative expenses increased		$ 100,000	$ 100,000
Iconix Australia
Schedule Of Investments [Line Items]
Percentage of ownership interest sold	45.00%
Non-controlling interest associated with join venture	$ 5,900,000