New Accounting Standards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity Attributable to Parent	$ 4,154.2		$ 7,659.3
Accounts and Financing Receivable, after Allowance for Credit Loss, Current	40.6		42.0
Accounts and Financing Receivable, after Allowance for Credit Loss		$ 2,526.7	2,534.1
Contract with Customer, Asset, Allowance for Credit Loss	1.0		2.5
Financial Asset Originated [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	156.7
Moody's, Ba2 Rating [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	133.0
Moody's, B3 Rating [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	23.7
Trade Accounts Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, after Allowance for Credit Loss, Current		2,283.3	2,287.1
Accounts Receivable, Allowance for Credit Loss	108.9	99.2
Accounts Receivable, Credit Loss Expense (Reversal)	54.3
Accounts Receivable, Allowance for Credit Loss, Writeoff	(46.9)
Accounts Receivable, Allowance for Credit Loss, Recovery	2.3
Loans Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, after Allowance for Credit Loss, Current		137.0	138.5
Loans and Leases Receivable, Allowance	8.5	9.5
Financing Receivable, Credit Loss, Expense (Reversal)	(0.1)
Allowance for Loan and Lease Losses, Write-offs	0.0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	(0.9)
Security deposit and other [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current		35.6	36.6
Security Deposits and Other Allowance for Credit Losses	1.1	1.6
Security Deposit and Other Credit Loss Expense (Reversal)	0.9
Security Deposits and Other Allowance for Credit Losses Writeoff	0.0
Security Deposit and Other Asset, Allowance for Credit Loss Recoveries	(1.4)
Held-to-maturity Securities [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt Securities, Available-for-sale and Held-to-maturity		70.8	71.9
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0.5	1.1
Debt Securities, Held-to-maturity, Credit Loss Expense (Reversal)	(0.6)
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Writeoff	0.0
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Recovery	0.0
Contract assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss		1,517.5	$ 1,520.0
Contract with Customer, Asset, Allowance for Credit Loss	1.0	5.0
Contract with Customer, Asset, Credit Loss Expense (Reversal)	(0.2)
Contract with Customer, Asset, Allowance for Credit Loss, Writeoff	0.0
Contract with Customer, Asset, Allowance for Credit Loss, Recovery	$ (3.8)
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts and Financing Receivable, after Allowance for Credit Loss		(7.4)
Accounting Standards Update 2016-13 [Member] | Trade Accounts Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, after Allowance for Credit Loss, Current		(3.8)
Accounting Standards Update 2016-13 [Member] | Loans Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, after Allowance for Credit Loss, Current		(1.5)
Accounting Standards Update 2016-13 [Member] | Security deposit and other [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current		(1.0)
Accounting Standards Update 2016-13 [Member] | Held-to-maturity Securities [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt Securities, Available-for-sale and Held-to-maturity		(1.1)
Accounting Standards Update 2016-13 [Member] | Contract assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss		(2.5)
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity Attributable to Parent		(7.8)
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] | Tax Deferred Asset Noncurrent [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity Attributable to Parent		2.1
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' Equity Attributable to Parent		$ (7.8)