Benefit Plans and Other Postretirement Benefits, Defined contribution plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Benefit Plans and Other Postretirement Benefits
Contributions to U.S. defined contribution plans by the Company, maximum percentage of eligible compensation	6.00%	6.00%	6.00%
Matching contributions to U.S. defined contribution plans by the Company	$ 16.2	$ 13.3	$ 13.1