Accounts Receivable, net (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Receivables [Abstract]
Contracts in progress	$ 306.0	$ 118.6
Unbilled retentions	99.8	50.3
Trade receivables	9.3	7.5
Other receivables	10.5	8.9
Allowance for doubtful accounts	(0.6)	(0.6)
Total	$ 425.0	$ 184.7

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

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- Definition

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.

+ References

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- Definition

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

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

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No definition available.

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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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