Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts and Bilinig Adjustments
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 5.1	$ 4.8	$ 8.5
Provisions	1.0	3.7	3.3
Deductions	(1.4)	(3.4)	(7.0)
Balance at end of year	4.7	5.1	4.8
Allowance for Workers' Compensation and Medical Malpractice Loss Reserves
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	16.2	17.4	14.8
Provisions	2.9	3.3	3.6
Deductions	(5.8)	(4.5)	(1.0)
Balance at end of year	$ 13.3	$ 16.2	$ 17.4

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

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Amount of decrease in valuation and qualifying accounts and reserves.

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