CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY - USD ($) $ in Millions	Total	ASC 326 Adoption Impact	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Retained Earnings ASC 326 Adoption Impact	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance at beginning of period at Dec. 31, 2021	$ 5,150.0		$ 107.0	$ 3.0	$ 4,109.0	$ 1,110.0		$ (62.0)	$ (117.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	144.0					439.0		(295.0)
Dividends declared:
Preferred stock	(8.0)					(8.0)
Common stock	(171.0)					(171.0)
Issuance of common stock	(6.0)				1.0				(7.0)
Issuance of common stock – acquisitions	570.0			1.0	569.0
Repurchase of common stock	(43.0)								(43.0)
Restricted stock compensation	17.0				17.0
Balance at end of period at Dec. 31, 2022	5,653.0		107.0	4.0	4,696.0	1,370.0		(357.0)	(167.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	607.0					485.0		122.0
Dividends declared:
Preferred stock	(8.0)					(8.0)
Common stock	(174.0)					(174.0)
Issuance of common stock	(10.0)				(22.0)	(4.0)			16.0
Repurchase of common stock	(36.0)								(36.0)
Restricted stock compensation	18.0				18.0
Balance at end of period at Dec. 31, 2023	$ 6,050.0	$ (1.0)	107.0	4.0	4,692.0	1,669.0	$ (0.5)	(235.0)	(187.0)
Dividends declared:
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2023-02 [Member]
Comprehensive income (loss)	$ 531.0					465.0		66.0
Preferred stock	(2.0)					(2.0)
Common stock	(175.0)					(175.0)
Redemption of preferred stock	(111.0)		(107.0)			(4.0)
Issuance of common stock	(4.0)				(14.0)				10.0
Repurchase of common stock	(3.0)								(3.0)
Restricted stock compensation	17.0				17.0
Balance at end of period at Dec. 31, 2024	$ 6,302.0		$ 0.0	$ 4.0	$ 4,695.0	$ 1,952.0		$ (169.0)	$ (180.0)