Affiliated Companies (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
Carrying amount, equity-method investments	$ 207.1		$ 207.1		$ 201.9
Carrying amount, investments not accounted for under the equity method	8.6		8.6		12.8
Purchases and royalty payments made to affiliates	34.0	$ 36.6	119.6	$ 97.0
Amount due and payable to affiliates	13.8		13.8		33.6
Sales to affiliates	2.8	$ 2.7	8.8	$ 7.7
Amount receivable from affiliates	$ 2.2		$ 2.2		$ 1.4