Fair Value Disclosure Fair Value Disclosure - Amounts Recorded on Balance Sheet Related to Cumulative Basis Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest Expense	$ (190.3)	$ (180.5)	$ (162.9)
Other Nonoperating Income (Expense)	(13.0)	(7.3)	(21.7)
Operating Lease, Expense	(49.3)	(54.4)	(49.6)
Recourse Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities)	5.6	1.4
Interest Expense [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain (loss) on non-designated derivative contracts		0.0	0.0
Interest Expense [Member] \| Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(4.2)	(9.0)	3.0
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	(4.2)	(9.0)	3.0
Other Nonoperating Income (Expense) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain (loss) on non-designated derivative contracts	6.2	(1.7)	2.2
Other Nonoperating Income (Expense) [Member] \| Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge		0.0	0.0
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments		0.0	0.0
Cash Flow Hedging [Member] \| Interest Expense [Member] \| Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(2.1)	(2.5)	(4.2)
Cash Flow Hedging [Member] \| Interest Expense [Member] \| Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		0.0	0.0
Cash Flow Hedging [Member] \| Other Nonoperating Income (Expense) [Member] \| Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		0.0	0.0
Cash Flow Hedging [Member] \| Other Nonoperating Income (Expense) [Member] \| Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (12.8)	14.3	11.7
Cash Flow Hedging [Member] \| Operating Expense [Member] \| Interest Rate Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		$ 0.0	$ (0.1)

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

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Amount of the cost of borrowed funds accounted for as interest expense.

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