Fair Value Disclosure - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) Instrument	Dec. 31, 2018 USD ($) Instrument	Dec. 31, 2017 USD ($)
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ 11.8	$ 7.4	$ (45.8)
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months	1.7
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months, net of tax	1.3
Derivative liability	13.6	30.6
Cash Flow Hedging [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), before Adjustments and Tax	(19.0)		41.5
Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), before Adjustments and Tax	0.5	0.0	2.2
Cash Flow Hedging [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), before Adjustments and Tax	$ (19.5)	$ (12.6)	39.3
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	8	9
Derivative liability	$ 450.0	$ 500.0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	7	8
Derivative liability	$ 336.5	$ 501.9
Not Designated as Hedging Instrument [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Derivative liability	7.6
Recourse Debt [Member]
Derivative [Line Items]
Hedged Asset, Fair Value Hedge	449.9	493.5
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	1.4	(7.7)
Other Nonoperating Income (Expense) [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	14.3	11.7	(38.9)
Interest Expense [Member]
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ (2.5)	$ (4.2)	$ (6.8)

Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Gross

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of asset hedged in fair value hedging relationship.

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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, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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