Stock Based Compensation - Components of Equity-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7.6	$ 3.8
Expected tax benefit	0.9	0.0
Restricted stock and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3.1	0.0
Expected tax benefit	0.5	0.0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1.5	0.0
Expected tax benefit	0.4	0.0
Incentive Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 3.0	$ 3.8