Accounts Receivable - Summary of Accounts Receivable (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract receivables	$ 58,193	$ 57,435
Allowance for doubtful accounts	(2,876)	(3,110)
Total accounts receivable	66,468	63,046
Trade Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade receivables	$ 11,151	$ 8,721