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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Face (par) amount of debt instrument at time of issuance.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Amount of increase in the fair value of derivatives recognized in the income statement.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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Fair value portion of notes payable.

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Amount, after tax, of cumulative translation adjustment attributable to gain (loss) on foreign currency derivatives that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

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Derivative Financial Instruments and Fair Value Measurements (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 EUR (€)	Dec. 31, 2016 USD ($)
Net investment hedges [Abstract]
Translation gain (loss) on net investment hedge	$ (13.9)		$ (13.9)			$ 24.8
Fair value measured on a recurring basis
Assets
Deferred compensation plan assets	94.4		94.4			86.8
Foreign currency forward contracts	0.1		0.1
Total assets measured at fair value	94.5		94.5			86.8
Liabilities
Foreign currency forward contracts	0.1		0.1			0.2
Total liabilities measured at fair value	0.1		0.1			0.2
Fair value measured on a recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Deferred compensation plan assets	94.4		94.4			86.8
Foreign currency forward contracts	0.0		0.0
Total assets measured at fair value	94.4		94.4			86.8
Liabilities
Foreign currency forward contracts	0.0		0.0			0.0
Total liabilities measured at fair value	0.0		0.0			0.0
Fair value measured on a recurring basis \| Significant Other Observable Inputs (Level 2)
Assets
Deferred compensation plan assets	0.0		0.0			0.0
Foreign currency forward contracts	0.1		0.1
Total assets measured at fair value	0.1		0.1			0.0
Liabilities
Foreign currency forward contracts	0.1		0.1			0.2
Total liabilities measured at fair value	0.1		0.1			0.2
Fair value measured on a recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Deferred compensation plan assets	0.0		0.0			0.0
Foreign currency forward contracts	0.0		0.0
Total assets measured at fair value	0.0		0.0			0.0
Liabilities
Foreign currency forward contracts	0.0		0.0			0.0
Total liabilities measured at fair value	0.0		0.0			0.0
Euro-denominated notes
Net investment hedges [Abstract]
Translation gain (loss) on net investment hedge	(9.7)		(9.7)			29.0
Forward contracts \| Designated as hedging instrument
Net investment hedges [Abstract]
Translation gain (loss) on net investment hedge	(4.2)		(4.2)			(4.2)
Forward contracts \| Not designated as hedging instrument
Net investment hedges [Abstract]
Loss associated with forward contracts included in interest and other expenses	0.0	$ 0.7		$ 1.3
Gain associated with forward contracts included in interest and other expenses			0.1
Fair value \| Euro-denominated notes \| Significant Other Observable Inputs (Level 2)
Liabilities
Carrying value of long-term debt	899.5		899.5			831.6
Carrying value \| Euro-denominated notes
Liabilities
Carrying value of long-term debt	853.8		853.8			$ 785.2
Notes due June 2018 \| Euro-denominated notes \| Designated as hedging instrument
Net investment hedges [Abstract]
Long-term debt	399.5		399.5		€ 350,000,000.0
Notes due September 2022 \| Euro-denominated notes \| Designated as hedging instrument
Net investment hedges [Abstract]
Long-term debt	$ 454.3		$ 454.3		€ 400,000,000