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Business and Summary of Significant Accounting Policies - Self-Insured Medical, Property and Casualty Reserves (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Estimated liability on incurred worker’s compensation and general liability claims	$ 24.0	$ 24.4

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- Definition

General Liability And Workers' Compensation Liability

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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