Leases (Lease Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease cost	$ 11.0	$ 10.9	$ 12.2
Variable lease cost	1.8	2.3	1.6
Total lease cost	$ 12.8	$ 13.2	$ 13.8