Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 306.6	$ 276.6	$ 284.0
Currency translation adjustments	(2.6)	(45.5)	99.8
Net unrealized pension and other benefit actuarial (losses) gains and prior service credits (net of tax)	(7.0)	3.1	(3.9)
Net unrealized (losses) gains on financial instruments (net of tax)	(1.1)	(22.2)	33.5
Total other comprehensive (loss) income	(10.7)	(64.6)	129.4
Comprehensive income	$ 295.9	$ 212.0	$ 413.4

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

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