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Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions | 12 Months Ended
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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

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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 + Details
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