Stock-based Compensation (Fair Value and Tax Deductions of Performance Share Units Distributed) (Details) - 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]
Undistributed And Unvested Performance Share Units	68,800
Realized tax benefits from tax deductions	$ 5.2	$ 0.6	$ 5.7
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares or units distributed	13.5	6.1	10.8
Realized tax benefits from tax deductions	$ 3.3	$ 1.5	$ 2.7