Affiliated Companies (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Purchases and royalty payments made to affiliates	$ 33.0	$ 16.3	$ 85.2	$ 64.0
Amount due and payable to affiliates	24.3		24.3		$ 12.9
Sales to affiliates	2.2	$ 3.0	6.9	$ 8.0
Amount receivable from affiliates	1.4		1.4		1.6
Carrying amount, equity-method investments	84.0		84.0		77.8
Carrying amount, cost-method investments	$ 13.4		$ 13.4		$ 13.4