Share-based Compensation Awards (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stock-based Payment Award
Vesting period in which the fair value of shares on grant date is amortized over, years	2 years
Stock-settled awards
Stock-based Payment Award
Awards granted	1.3	0.9	2.3
Weighted-average grant-date fair value (per award)	$ 36.36	$ 26.96	$ 20.70
Total fair value of vested awards distributed	$ 59.7	$ 50.8	$ 17.3
Accrued dividends on non-vested stock-settled awards	3.7	3.6
Dividends paid for stock-settled awards	$ 4.9	$ 4.3
Cash-settled awards
Stock-based Payment Award
Awards granted	0.0	0.0	0.0
Weighted-average grant-date fair value (per award)	$ 36.53	$ 0	$ 21.02
Total fair value of vested awards distributed	$ 0.8	$ 0.7	$ 0.3
Performance-based awards
Stock-based Payment Award
Awards granted	1.6	0.5	2.4
Weighted-average grant-date fair value (per award)	$ 29.95	$ 21.98	$ 18.67
Total fair value of vested awards distributed	$ 54.5	$ 39.3	$ 53.3