Accumulated Other Comprehensive Income (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Cost of products sold		$ (346.5)	$ (354.0)	$ (961.2)	$ (924.1)
Income before income tax		49.0	49.8	99.1	88.0
Income tax (expense) benefit		(13.4)	(19.2)	(27.4)	(30.3)
Net income		35.6	30.6	71.7	57.7
Amount Reclassified from Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Net income		(2.9)	(2.3)	(7.4)	(3.0)
Unrecognized Pension and Other Post-retirement Benefit Costs | Amount Reclassified from Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial loss	[1]	(1.4)	(1.1)	(4.3)	(3.4)
Amortization of prior service cost	[1]	(0.1)	(0.1)	(0.3)	(0.3)
Income before income tax		(1.5)	(1.2)	(4.6)	(3.7)
Income tax (expense) benefit		0.4	0.2	1.1	1.0
Net income		(1.1)	(1.0)	(3.5)	(2.7)
Foreign exchange contracts | Derivative Financial Instruments | Amount Reclassified from Accumulated Other Comprehensive Income
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Cost of products sold		(2.6)	(1.9)	(5.5)	(0.3)
Income tax (expense) benefit		0.8	0.6	1.6	0.0
Net income		$ (1.8)	$ (1.3)	$ (3.9)	$ (0.3)

[1] These accumulated other comprehensive income components are included in the computation of net periodic benefit cost for pension and post-retirement plans. See "Note 6. Pension and Other Retiree Benefits" for additional details.