Stockholder's Equity (Reclassification out of Other Comprehensive Income) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Reclassification out of Accumulated Other Comprehensive Income
Revenue		$ 2,913.0	$ 3,125.2
Selling, general and administrative expense		(297.8)	(303.1)
Other income (expense), net		(26.2)	(25.2)
Income (loss) before income taxes	[1]	34.3	140.7
Provision for income taxes (Note 17)		14.5	49.3
Net income (loss)		19.8	91.4
Amount Reclassified out of Accumulated Other Comprehensive Loss
Reclassification out of Accumulated Other Comprehensive Income
Amortization of prior service credit (cost)	[2]	(0.4)
Income (loss) before income taxes		(0.4)
Provision for income taxes (Note 17)		(0.1)
Net income (loss)		(0.3)
Foreign exchange contracts | Amount Reclassified out of Accumulated Other Comprehensive Loss | Hedging
Reclassification out of Accumulated Other Comprehensive Income
Provision for income taxes (Note 17)		0.7	(0.2)
Net income (loss)		0.3	(0.2)
Foreign exchange contracts | Cash Flow Hedging | Amount Reclassified out of Accumulated Other Comprehensive Loss | Hedging
Reclassification out of Accumulated Other Comprehensive Income
Revenue		0.7	2.5
Cost of sales		2.6	1.6
Selling, general and administrative expense		0.1	0.1
Other income (expense), net		(2.4)	(4.6)
Income (loss) before income taxes		$ 1.0	$ (0.4)

[1] Includes amounts attributable to noncontrolling interests.

[2] These accumulated other comprehensive income components are included in the computation of net periodic pension cost.