Stock-Based Compensation - Components of Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-Based Payment Arrangement [Abstract]
Equity classified awards expense	$ 4.0	$ 2.5	$ 8.4	$ 5.6
Liability classified awards expense	1.0	0.5	1.4	2.0
Total pre-tax stock-based compensation expense	5.0	3.0	9.8	7.6
Book income tax benefit	(1.2)	(0.8)	(2.4)	(1.9)
Total stock-based compensation expense, net of tax	$ 3.8	$ 2.2	$ 7.4	$ 5.7