Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Total net sales	$ 1,196.4	$ 1,166.7	$ 2,283.7	$ 2,157.9
Cost of goods sold	(839.0)	(818.8)	(1,619.0)	(1,527.1)
Income before income taxes	123.6	134.0	221.6	209.8
Tax benefit (expense)	(25.7)	(31.6)	(49.9)	(47.6)
Gain (loss) net of tax	97.9	102.4	171.7	162.2
Gain (loss) net of tax	(1.6)	(1.9)	(2.8)	(4.1)
Cash flow hedge (loss) gain
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Gain (loss) net of tax			0.6
Prior-service costs
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Amortization of defined benefit pension and post retirement benefit items	0.2	0.3	0.4	0.5
Actuarial gains/(losses)
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Amortization of defined benefit pension and post retirement benefit items	(2.7)	(2.8)	(4.9)	(5.6)
Pension and post retirement benefit plan adjustment
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Amortization of defined benefit pension and post retirement benefit items	(2.5)	(2.5)	(4.5)	(5.1)
Tax benefit (expense)	0.6	0.6	1.1	1.2
Gain (loss) net of tax	(1.9)	(1.9)	(3.4)	(3.9)
Forward Contracts | Cash flow hedge (loss) gain | Reclassification out of Accumulated Other Comprehensive Income
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax [Abstract]
Total net sales	0.1	(0.1)	0.3	(0.1)
Cost of goods sold	0.2	0.0	0.5	(0.2)
Income before income taxes	0.3	(0.1)	0.8	(0.3)
Tax benefit (expense)	0.0	0.1	(0.2)	0.1
Gain (loss) net of tax			$ 0.6	$ (0.2)
Gain (loss) net of tax	$ 0.3	$ 0.0