Earnings per Share - Schedule of Calculation of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Calculation of basic earnings (loss) per share:
Net income (loss) applicable to common stock	$ (26.8)	$ 78.2	$ (141.5)	$ 591.2
Weighted-average common shares outstanding - basic (in shares)	152.1	152.8	152.0	153.0
Basic earnings (loss) per share (in dollars per share)	$ (0.18)	$ 0.51	$ (0.93)	$ 3.86
Calculation of diluted earnings (loss) per share:
Net income (loss) applicable to common stock	$ (26.8)	$ 78.2	$ (141.5)	$ 591.2
Convertible Notes	0.0	1.8	0.0	3.6
Diluted income (loss) applicable to common stock	$ (26.8)	$ 80.0	$ (141.5)	$ 594.8
Weighted average common shares outstanding - diluted (in shares)	152.1	167.9	152.0	168.2
Diluted earnings (loss) per share (in dollars per share)	$ (0.18)	$ 0.48	$ (0.93)	$ 3.54
Effective tax rate	(91.00%)		19.40%
Convertible Notes
Calculation of diluted earnings (loss) per share:
Effective tax rate		21.00%		21.00%
Common Stock, Non-Exchangeable
Calculation of basic earnings (loss) per share:
Weighted-average common shares outstanding - basic (in shares)	151.6	152.2	151.5	152.4
Common Stock, Exchangeable
Calculation of basic earnings (loss) per share:
Weighted-average common shares outstanding - basic (in shares)	0.5	0.6	0.5	0.6