CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 111.5	$ 122.4
Other comprehensive income before tax:
Change in cumulative translation adjustments	20.8	91.6
Net change in cash flow hedges		0.4
Net change in unrealized components of defined benefit plans	0.1	0.8
Other comprehensive income, before tax	20.9	92.8
Tax effect allocated to other comprehensive income	0.0	(0.2)
Other comprehensive income, net of tax	20.9	92.6
Comprehensive income	132.4	215.0
Less: Comprehensive income attributable to non-controlling interest	0.4	1.5
Comprehensive income attributable to controlling interest	$ 132.0	$ 213.5