Contract Assets and Liabilities - Summary of contract assets (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Contractors [Line Items]
Unbilled revenue, net	$ 135,289		$ 126,087
Contract retainages, net	88,986		91,022
Contract assets, net	224,275		$ 217,109
Changes in contract assets, net	7,658	$ 14,218
Net Period Change [Member]
Contractors [Line Items]
Changes in unbilled revenue, net	9,202
Changes in contract retainages, net	(2,036)
Changes in contract assets, net	$ 7,166

n/a

No definition available.

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The increase (decrease) during the reporting period of the amount of contract receivable retainage.

+ References

No definition available.

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The amount of contract with customer, increase (decrease) during the reporting period of the amount of revenue for work performed for which billing has not occurred, net of uncollectible accounts.

+ References

No definition available.

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Amount of right to consideration in exchange for good or service transferred to customer withheld under retainage provision in long-term contract or program when right to consideration is unconditional.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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- Definition

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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