Accrued Warranty Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Changes in product warranty liability [Roll Forward]
Balance at beginning of period	$ 6.2	$ 7.9
Claims paid	(0.8)	(1.6)
Warranty expense	1.3	1.6
Balance at end of period	$ 6.7	$ 7.9