Other Assets - Current (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
US federal tax receivables		$ 1,115
Insurance receivable		15,000
Prepaid advertising	$ 209	275
Prepaid expenses	678	1,207
Prepaid income taxes	457	1,119
Prepaid insurance	372	2,042
Due from related parties	86	86
Other prepaid taxes	474	596
Other current assets	$ 2,276	$ 21,440