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Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Impaired Long Lived Assets Held And Used [Line Items]
Impairment of long-lived assets		$ 0	$ 0
Impairment of equity method investment		19,607,000	26,613,000
Payments to acquire ownership interest		2,750,000
Contract asset impairment		4,467,000	5,143,000
Ecko Mark/Ecko and Candies Joint Venture \| China
Impaired Long Lived Assets Held And Used [Line Items]
Impairment of equity method investment		19,600,000
MG Icon
Impaired Long Lived Assets Held And Used [Line Items]
Impairment of equity method investment	$ 9,600,000		9,600,000
Payments to acquire ownership interest	$ 2,600,000		2,600,000
Marcy Media Holdings
Impaired Long Lived Assets Held And Used [Line Items]
Impairment of equity method investment			17,000,000
New York Office Space
Impaired Long Lived Assets Held And Used [Line Items]
Contract asset impairment		$ 100,000	$ 1,800,000