Benefit Plans Benefit Plans - Defined Contribution Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Contribution Plan [Line Items]
Defined Contribution Plan, Cost	$ 6.9	$ 0.7	$ 10.3
Retirement savings plan basic match	50.00%
Employee Contributions First Six Percent [Member]
Defined Contribution Plan [Line Items]
Participant Contribution Percentage	6.00%