Schedule of Accounts Receivable (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Receivables [Abstract]
Billed and billable	$ 151,234	$ 165,153
Less: allowance for credit losses	(2,722)	(1,637)
Accounts receivable, net	$ 148,512	$ 163,516

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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