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Contingencies (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) superfundSites
Commitments and Contingencies Disclosure [Abstract] |
Number of Superfund sites for which company may be liable | superfundSites | 1
Workers' compensation deductible (per occurrence) | $ 1.0
General liability insurance deductible | 3.0
Auto liability insurance deductible | 0.3
Workers' compensation accrued liability | 27.8
Outstanding letters of credit | $ 13.0

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