Revenue Recognition - Impact on Statement of Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Sales	$ 409.2	$ 344.5
Cost of sales	305.6	246.9
Gross profit	103.6
Income tax provision (benefit)	0.4	(0.5)
Net income	1.2	$ 17.4
Balances without Adoption
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Sales	358.7
Cost of sales	268.1
Gross profit	90.6
Income tax provision (benefit)	(2.9)
Net income	(8.5)
Accounting Standards Update 2014-09 | Adjustments due to Topic 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Sales	(50.5)
Cost of sales	(37.5)
Gross profit	(13.0)
Income tax provision (benefit)	(3.3)
Net income	$ (9.7)