Accumulated Other Comprehensive Income (Loss) - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net interest expense	$ 13.6	$ 9.4	$ 6.8
Provision for income taxes	50.1	26.0	$ 26.2
Selling, General and Administrative Expenses
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments from AOCI into earnings for pension and other postretirement benefits plans	(4.8)	(4.1)
Provision for Income Taxes
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments from AOCI into earnings for pension and other postretirement benefits plans	2.0	1.6
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net interest expense	1.2	1.3
Provision for income taxes	$ 0.5	$ 0.5