Share-Based Compensation and Equity - Share-based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Pre-tax compensation expense	$ 13.8	$ 14.9	$ 24.0
Tax benefit	(3.6)	(3.7)	(5.6)
Total share-based compensation, net of tax	10.2	11.2	18.4
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Pre-tax compensation expense	1.5	1.7	1.5
Tax benefit	(0.4)	(0.5)	(0.2)
Total share-based compensation, net of tax	1.1	1.2	1.3
Restricted Stock Units [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Pre-tax compensation expense	8.7	8.9	11.6
Tax benefit	(2.2)	(2.2)	(2.5)
Total share-based compensation, net of tax	6.5	6.7	9.1
Performance Shares [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Pre-tax compensation expense	3.6	4.3	10.9
Tax benefit	(1.0)	(1.0)	(2.9)
Total share-based compensation, net of tax	$ 2.6	$ 3.3	$ 8.0