Related Party Transactions - Summary of Royalty Revenue Recognized (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Related Party Transaction [Line Items]
Royalty revenue		$ 24,462	$ 35,471	$ 74,688	$ 105,806
Royalty
Related Party Transaction [Line Items]
Royalty revenue		1,131	1,164	3,671	3,233
Royalty | Li Ning
Related Party Transaction [Line Items]
Royalty revenue		207		393
Royalty | M.G.S. Sports Trading Limited
Related Party Transaction [Line Items]
Royalty revenue		102	111	309	329
Royalty | Pac Brands USA, Inc.
Related Party Transaction [Line Items]
Royalty revenue		46	131	153	239
Royalty | Albion Equity Partners LLC / GL Damek
Related Party Transaction [Line Items]
Royalty revenue		565	615	1,711	1,777
Royalty | MHMC
Related Party Transaction [Line Items]
Royalty revenue	[1]				7
Royalty | Sports Direct International plc
Related Party Transaction [Line Items]
Royalty revenue		$ 211	$ 307	$ 1,105	$ 881

[1] As detailed in Note 4, as of July 2019, MHMC is no longer a related party.