Revenue Recognition - Schedule of Disaggregated Revenue by Source (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Net services revenue	$ 385.7	$ 342.6
Net operating fees
Disaggregation of Revenue [Line Items]
Net services revenue	322.8	286.1
Incentive fees
Disaggregation of Revenue [Line Items]
Net services revenue	30.2	29.0
Other
Disaggregation of Revenue [Line Items]
Net services revenue	$ 32.7	$ 27.5