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Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Reserve For Accounts Receivable [Member] |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Beginning Balance | $ 19.2 | $ 21.1 | $ 18.3
Valuation Allowances and Reserves, Charged to Cost and Expense | 31.6 | 21.6 | 20.2
Valuation Allowances and Reserves, Charged to Other Accounts | 33.0 | 41.3 | 43.7
Deductions for Purposes for which Reserves were Created | 31.5 | 64.8 | 61.1
Ending Balance | 52.3 | 19.2 | 21.1
Reserve For Other Investments [Member] |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Beginning Balance | 3.0 | 3.0 | 3.0
Valuation Allowances and Reserves, Charged to Cost and Expense | 0.0 | 0.0 | 0.0
Valuation Allowances and Reserves, Charged to Other Accounts | 0.0 | 0.0 | 0.0
Deductions for Purposes for which Reserves were Created | 3.0 | 0.0 | 0.0
Ending Balance | $ 0.0 | $ 3.0 | $ 3.0

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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(Column B)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 Reference 2: 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(Column E)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + 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(Column C)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense. + 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(Column C)(2)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
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