Employee Benefit Plans (Contributions to Defined Contribution Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 15, 2019	Apr. 03, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contributions to defined contribution plans	$ 17.8	$ 19.1	$ 18.8
Transfer of pension plan asset to life insurance company				$ 73.5	$ 100.0
UNITED STATES
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Projected Benefit Obligation By Pension Plans	82.00%
Plan assets (as a percent)	75.00%