Accounts Receivable and Allowance for Doubtful Accounts - Schedule of Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Receivables [Abstract]
Trade accounts receivable	$ 182,015	$ 174,604
Costs in excess of billings	48,594	26,915
Total accounts receivables	230,609	201,519
Less allowance for doubtful accounts and contract assets	(5,294)	(3,529)
Accounts receivable, net	$ 225,315	$ 197,990

Contracts Receivable, Gross, Current

No definition available.

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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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Unbilled amounts due for 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 entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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