Accounts Receivable, Net - Accounts Receivables Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounts Receivable Net Current [Abstract]
Trade accounts receivable	$ 197,725	$ 176,375
Unbilled revenue, at net realizable value	85,845	60,035
Total accounts receivable	283,570	236,410
Allowance for doubtful accounts	(16,372)	(14,379)
Accounts receivable, net	$ 267,198	$ 222,031

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

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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.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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