Stock-based Compensation (Restricted Stock Units) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 30.1	$ 21.8	$ 24.3
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 10.8	$ 11.0	$ 8.7
Weighted-average fair value of grants, per share (in usd per share)	$ 0	$ 240.87	$ 315.70
Award service period	3 years