Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net sales	$ 1,037.9	$ 1,108.6	$ 949.2	$ 1,090.3	$ 1,103.3	$ 1,204.0	$ 1,196.4	$ 1,087.3	$ 4,186.0	$ 4,591.0	$ 4,481.7
Cost of goods sold	752.2	779.0	668.7	776.8	777.3	842.0	839.0	780.0	2,976.7	3,238.3	3,181.3
Income before income taxes									453.5	520.5	467.0
Other expense, net									(11.6)	(21.4)	(17.6)
Gain on disposition of business (Note 3)									0.0	21.7	0.0
Provision for income taxes									(97.5)	(113.1)	(100.9)
Net income	$ 82.6	$ 108.6	$ 89.1	$ 75.7	$ 103.1	$ 132.6	$ 97.9	$ 73.8	356.0	407.4	$ 366.1
Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income									(12.2)	(0.6)
Cash flow hedges gain (loss) | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net sales									0.3	0.3
Cost of goods sold									0.5	0.4
Income before income taxes									0.8	0.7
Provision for income taxes									(0.2)	(0.2)
Net income									0.6	0.5
Amortization of defined benefit pension and post retirement benefit items | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									(17.0)	(9.3)
Provision for income taxes									4.2	2.3
Net income									(12.8)	(7.0)
Prior-service costs | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									0.2	0.7
Actuarial gains/(losses) | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									(9.7)	(9.7)
Settlement and curtailment losses | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									(7.5)	(0.3)
Reclassification of gains (losses) on available-for-sale securities | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other expense, net									0.0	(1.8)
Provision for income taxes									0.0	0.0
Net income									0.0	(1.8)
Reclassification of currency translation gain | Reclassification out of accumulated other comprehensive income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain on disposition of business (Note 3)									0.0	7.7
Provision for income taxes									0.0	0.0
Net income									$ 0.0	$ 7.7