Share-Based Compensation (Compensation Expenses) (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]
Share-based compensation expense	$ (67.1)	$ (55.7)	$ (67.7)
Tax benefit	(16.3)	(13.5)	(16.4)
Share-based compensation expense, net of tax	(50.8)	(42.2)	(51.3)
Deferred Compensation, Share-based Payments
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	(4.3)	(1.2)	(3.0)
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	(16.1)	(14.1)	(16.7)
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	(23.5)	(19.7)	(21.9)
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	(23.2)	(20.7)	(26.1)
Segment, Continuing Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, net of tax	(50.8)	(42.6)	(51.3)
Segment, Discontinued Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, net of tax	$ 0.0	$ (0.4)	$ 0.0