CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions		Total	Preferred Stock	Common Stock, $0.0001 Par Value		Additional Paid in Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning balance (shares) at Dec. 31, 2021			12,000,000.0	106,600,000
Beginning balance at Dec. 31, 2021		$ 4,962.6	$ 294.5	$ 0.0		$ 1,966.2	$ (86.8)	$ 15.7	$ 2,773.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		1,057.3							1,057.3
Restricted stock, performance stock units, and other grants, net (shares)				600,000
Restricted stock, performance stock units, and other grants, net		$ 39.8				39.8
Restricted stock surrendered (shares)		(200,745)		(200,000)	[1]
Restricted stock surrendered	[1]	$ (18.5)					(18.5)
Stock issuance, net (shares)				1,900,000
Stock issuance, net				$ 157.7		157.7
Dividends paid to preferred stockholders		(12.8)							(12.8)
Dividends paid to common stockholders		(153.4)							(153.4)
Other comprehensive income, net		(676.7)						(676.7)
Ending balance at Dec. 31, 2022		5,356.0	$ 294.5	$ 0.0		2,163.7	(105.3)	(661.0)	3,664.1
Ending balance (shares) at Dec. 31, 2022			12,000,000.0	108,900,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		722.4							722.4
Restricted stock, performance stock units, and other grants, net (shares)				700,000
Restricted stock, performance stock units, and other grants, net		$ 34.4				34.4
Restricted stock surrendered (shares)		(152,452)		(200,000)	[1]
Restricted stock surrendered	[1]	$ (11.0)					(11.0)
Dividends paid to preferred stockholders		(12.8)							(12.8)
Dividends paid to common stockholders		(158.7)							(158.7)
Other comprehensive income, net		148.1						148.1
Ending balance at Dec. 31, 2023		6,078.4	$ 294.5	$ 0.0		2,198.1	(116.3)	(512.9)	4,215.0
Ending balance (shares) at Dec. 31, 2023			12,000,000.0	109,400,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		787.7							787.7
Restricted stock, performance stock units, and other grants, net (shares)				700,000
Restricted stock, performance stock units, and other grants, net		$ 47.7				47.7
Restricted stock surrendered (shares)		(141,983)		(100,000)	[1]
Restricted stock surrendered	[1]	$ (8.7)					(8.7)
Dividends paid to preferred stockholders		(12.8)
Dividends paid to common stockholders		(164.0)							(164.0)
Other comprehensive income, net		(20.8)						(20.8)
Ending balance at Dec. 31, 2024		$ 6,707.5	$ 294.5	$ 0.0		$ 2,245.8	$ (125.0)	$ (533.7)	$ 4,825.9
Ending balance (shares) at Dec. 31, 2024			12,000,000.0	110,000,000.0

[1] Share amounts represent treasury shares, see "Note 1. Summary of Significant Accounting Policies" for further discussion.