Share-Based Compensation - Compensation Expense for Share-Based Awards (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 9.5	$ 9.2	$ 24.8	$ 21.6
Income tax benefit	(2.4)	(2.3)	(6.2)	(5.5)
Share-based compensation expense, net of tax benefit	7.1	6.9	18.6	16.1
Restricted Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense	5.6	5.4	17.5	14.7
Performance Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 3.9	$ 3.8	$ 7.3	$ 6.9