Earnings per Share - Calculation of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Calculation of basic earnings per share:
Net income applicable to common stock	$ 512.8	$ 51.5
Weighted-average common shares outstanding - basic (in shares)	153.3	168.2
Basic earnings per share (in dollars per share)	$ 3.35	$ 0.31
Calculation of diluted earnings per share:
Net income applicable to common stock	$ 512.8	$ 51.5
Convertible Notes	1.8	1.8
Diluted income applicable to common stock	$ 514.6	$ 53.3
Weighted average common shares outstanding - diluted (in shares)	168.6	184.2
Diluted earnings per share (in dollars per share)	$ 3.05	$ 0.29
Effective tax rate	23.80%	48.00%
Convertible Notes
Calculation of diluted earnings per share:
Effective tax rate	21.00%	20.00%
Common Stock, Non-Exchangeable
Calculation of basic earnings per share:
Weighted-average common shares outstanding - basic (in shares)	152.7	167.5
Common Stock, Exchangeable
Calculation of basic earnings per share:
Weighted-average common shares outstanding - basic (in shares)	0.6	0.7