Commitments and Contingencies - Other and Bonds (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) item
Obligation to perform subcontract work \| Pending Litigation
Commitments and Contingencies
Letter of intent under dispute \| item	2
Damages stated	$ 9
Obligation to perform subcontract work \| Customer \| Pending Litigation
Commitments and Contingencies
Damages claimed	$ 15
Surety \| Minimum
Surety
Percentage of business which has required bonds	15.00%
Surety \| Maximum
Surety
Percentage of business which has required bonds	25.00%

The value (monetary amount) of the award the defendant stated in the legal matter.

No definition available.

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- Definition

The total number of letter of intent executed to perform subcontract work under dispute pertaining to a loss contingency during the period.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

Represents the percentage of business which has required bonds.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
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-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

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-Name Accounting Standards Codification
-Topic 450
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-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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