Accounts Receivable - Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Trade	$ 86,659	$ 85,284
Less—allowance for credit losses	2,044	2,044	$ 2,517	$ 2,339
Accounts receivable, net	$ 84,615	$ 83,240