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Accounts Receivable and Allowance for Doubtful Accounts - Schedule of Receivables (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
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Receivables [Abstract] |  |
Trade accounts receivable | $ 175,251 | $ 133,238
Costs in excess of billings | 24,628 | 20,607
Total accounts receivables | 199,879 | 153,845
Less allowance for doubtful accounts and contract assets | (6,270) | (6,330)
Accounts receivable | $ 193,609 | $ 147,515

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