Consolidated Statements of Shareholders' Equity - USD ($) $ in Millions	Total	Period of Adoption Adjustment	[1]	Series B Preferred Stock	Series C Preferred Stock	Series D Preferred Stock	Preferred Shares	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Retained Earnings Period of Adoption Adjustment	[1]	Retained Earnings Series B Preferred Stock	Retained Earnings Series C Preferred Stock	Retained Earnings Series D Preferred Stock
Beginning Balance at Dec. 31, 2019	$ 23,071	$ (882)					$ 0	$ 163	$ 11,774	$ (2,737)	$ 13,871	$ (882)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,135										3,135
Other comprehensive (loss) income	(158)									(158)
Repurchase of common shares	(875)							(2)	(105)		(768)
Other changes, primarily employee plans	164								212		(48)
Cash dividends declared preferred				$ (34)	$ (45)									$ (34)	$ (45)
Cash dividends declared common	(1,392)										(1,392)
Ending Balance at Dec. 31, 2020	22,984						0	161	11,881	(2,895)	13,837
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	8,060										8,060
Other comprehensive (loss) income	(50)									(50)
Preferred shares issued	1,584								1,584
Redemption of preferred shares	(1,600)								(1,584)		(16)
Repurchase of common shares	(7,598)							(9)	(631)		(6,958)
Other changes, primarily employee plans	227							1	245		(19)
Cash dividends declared preferred				$ (27)	$ (23)	$ (21)								$ (27)	$ (23)	$ (21)
Cash dividends declared common	(1,359)										(1,359)
Ending Balance at Dec. 31, 2021	22,177						0	153	11,495	(2,945)	13,474
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	7,514										7,514
Other comprehensive (loss) income	(265)									(265)
Repurchase of common shares	(3,332)							(4)	(302)		(3,026)
Other changes, primarily employee plans	242								300		(58)
Cash dividends declared preferred						$ (57)										$ (57)
Cash dividends declared common	(1,568)										(1,568)
Ending Balance at Dec. 31, 2022	$ 24,711						$ 0	$ 149	$ 11,493	$ (3,210)	$ 16,279

[1] Represents $1,170 million, net of tax of $288 million, related to the impact as of January 1, 2020 of adopting the Current Expected Credit Loss (CECL) methodology for the recognition of credit losses on certain financial instruments.