Revenue from Contracts with Customers - Contracts In Progress (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue earned on uncompleted contracts	$ 718,366	$ 752,564
Less: Billings to date	(715,111)	(766,690)
Net underbilling (overbilling)	3,255	(14,126)
Costs in excess of billings and estimated earnings	39,772	31,894
Billings in excess of costs and estimated earnings	$ (36,517)	$ (46,020)

Billings In Excess Of Billings And Estimated Earnings On Uncompleted Contracts

No definition available.

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The amount of billings that were raised on the contracts to date during the period.

No definition available.

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Costs In Excess Of Billings And Estimated Earnings On Uncompleted Contracts

No definition available.

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The amount of Asset or liability for net Under Over billings on the contracts.

No definition available.

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The amount of revenue earned from uncompleted contracts during the period.

No definition available.

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No definition available.

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