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Employee Benefit Plans - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) union	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Multiemployer Plans, Pension
Number of local unions (union) | union	300
United States | Profit Sharing and Thrift Employee Benefit Plan | Other Postretirement Benefits Plan
Contributions to benefit plans | $	$ 16.8	$ 10.9	$ 5.8

X

- Definition

Represents the number of local unions.

+ References

No definition available.

+ Details

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X

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Details

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- Details

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- Details

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- Details

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