Fair Value Disclosure Fair Value Disclosure - Impact of Cash Flow and Hedge Accounting Relationships (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest expense, net	$ (47.1)	$ (42.2)	$ (93.6)	$ (82.1)
Other (expense) income	(0.6)	(9.8)	(3.8)	(11.1)
Interest Expense [Member]
Gain (loss) on fair value hedging relationships
Gain (loss) on non-designated derivative contracts	0.0	0.0	0.0	0.0
Interest Expense [Member] \| Interest Rate Contract [Member]
Gain (loss) on fair value hedging relationships
Hedged items	(5.3)	1.8	(8.5)	7.6
Derivatives designated as hedging instruments	5.3	(1.8)	8.5	(7.6)
Interest Expense [Member] \| Interest Rate Contract [Member] \| Cash Flow Hedging [Member]
Gain (loss) on fair value hedging relationships
Amount of gain (loss) reclassified from accumulated other comprehensive income into income	(0.7)	(1.1)	(1.5)	(2.2)
Interest Expense [Member] \| Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member]
Gain (loss) on fair value hedging relationships
Amount of gain (loss) reclassified from accumulated other comprehensive income into income	0.0	0.0	0.0	0.0
Other (Income) Expense [Member]
Gain (loss) on fair value hedging relationships
Gain (loss) on non-designated derivative contracts	(1.9)	5.0	(2.7)	5.7
Other (Income) Expense [Member] \| Interest Rate Contract [Member]
Gain (loss) on fair value hedging relationships
Hedged items	0.0	0.0	0.0	0.0
Derivatives designated as hedging instruments	0.0	0.0	0.0	0.0
Other (Income) Expense [Member] \| Interest Rate Contract [Member] \| Cash Flow Hedging [Member]
Gain (loss) on fair value hedging relationships
Amount of gain (loss) reclassified from accumulated other comprehensive income into income	0.0	0.0	0.0	0.0
Other (Income) Expense [Member] \| Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member]
Gain (loss) on fair value hedging relationships
Amount of gain (loss) reclassified from accumulated other comprehensive income into income	$ (5.9)	$ 16.3	$ 5.1	$ 8.1

Change in Unrealized Gain (Loss) on Fair Value Value Hedge [Abstract]

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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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