Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 80.1	$ 69.7	$ 210.5	$ 195.9
Currency translation adjustments	(0.4)	28.7	(26.2)	87.2
Net unrealized pension and other benefit actuarial gains and prior service credits	(0.6)	(0.6)	(0.1)	(1.6)
Net unrealized gains (losses) on financial instruments (net of tax)	0.2	7.7	(11.9)	31.6
Total other comprehensive income	(0.8)	35.8	(38.2)	117.2
Comprehensive income	$ 79.3	$ 105.5	$ 172.3	$ 313.1

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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