Stock Based Compensation (RSU Activity) (Details) - Long-Term Equity Incentive Plan - Restricted Stock Units - USD ($) $ 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	$ 31.7	$ 34.9	$ 32.8
Income tax benefit	(6.0)	(6.4)	(5.9)
Share-based compensation expense, net of tax	$ 25.7	$ 28.5	$ 26.9