Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred Shares	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Series D Preferred Stock	Series D Preferred Stock Retained Earnings
Beginning Balance at Dec. 31, 2022	$ 24,711	$ 0	$ 149	$ 11,493	$ (3,210)	$ 16,279
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,816					1,816
Other comprehensive (loss) income	104				104	0
Repurchase of common shares	(195)			(17)		(178)
Other changes, including employee plans	20			46		(26)
Cash dividends declared preferred							$ (14)	$ (14)
Cash dividends declared common	(450)					(450)
Ending Balance at Mar. 31, 2023	25,992	0	149	11,522	(3,106)	17,427
Beginning Balance at Dec. 31, 2023	28,057	0	145	11,372	(3,072)	19,612
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,437					2,437
Other comprehensive (loss) income	(83)				(83)	0
Repurchase of common shares	(1,136)		(1)	(83)		(1,052)
Other changes, including employee plans	10			65		(55)
Cash dividends declared preferred							$ (14)	$ (14)
Cash dividends declared common	(507)					(507)
Ending Balance at Mar. 31, 2024	$ 28,764	$ 0	$ 144	$ 11,354	$ (3,155)	$ 20,421