CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (unaudited) - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	[1]	Cumulative Effect, Period of Adoption, Adjusted Balance	Series H Preferred Stock	Series I Preferred Stock	Series J Preferred Stock	Series K Preferred Stock	Series L Preferred Stock	Class B, Series A Preferred Stock	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Preferred Stock	Preferred Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Capital Surplus	Capital Surplus Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	[1]	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings Series H Preferred Stock	Retained Earnings Series I Preferred Stock	Retained Earnings Series J Preferred Stock	Retained Earnings Series K Preferred Stock	Retained Earnings Series L Preferred Stock	Retained Earnings Class B, Series A Preferred Stock	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning balance at Dec. 31, 2021	$ 22,210										$ 2,051		$ 2,116		$ 3,624		$ 20,236										$ 1,207		$ (7,024)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	1,709																1,709
Other comprehensive income (loss), net of tax	(6,513)																										(6,513)
Cash dividends declared:
Common stock	(648)																(648)
Preferred stock					$ (15)	$ (23)	$ (10)	$ (9)	$ (12)	$ (9)											$ (15)	$ (23)	$ (10)	$ (9)	$ (12)	$ (9)
Impact of stock transactions under stock compensation plans, net	56														36														20
Ending balance at Sep. 30, 2022	16,736										2,051		2,116		3,660		21,219										(5,306)		(7,004)
Beginning balance at Dec. 31, 2021	22,210										2,051		2,116		3,624		20,236										1,207		(7,024)
Ending balance at Dec. 31, 2022	$ 17,327	$ 37		$ 17,364							2,051	$ 2,051	2,116	$ 2,116	3,684	$ 3,684	21,689	$ 37		$ 21,726							(5,110)	$ (5,110)	(7,103)	$ (7,103)
Cash dividends declared:
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2022-02
Beginning balance at Jun. 30, 2022	$ 18,970										2,051		2,116		3,636		20,818										(2,644)		(7,007)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	653																653
Other comprehensive income (loss), net of tax	(2,662)																										(2,662)
Cash dividends declared:
Common stock	(230)																(230)
Preferred stock						(8)	(4)	(3)	(4)	(3)												(8)	(4)	(3)	(4)	(3)
Impact of stock transactions under stock compensation plans, net	27														24														3
Ending balance at Sep. 30, 2022	16,736										2,051		2,116		3,660		21,219										(5,306)		(7,004)
Beginning balance at Dec. 31, 2022	17,327	$ 37		$ 17,364							2,051	$ 2,051	2,116	$ 2,116	3,684	$ 3,684	21,689	$ 37		$ 21,726							(5,110)	$ (5,110)	(7,103)	$ (7,103)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	1,819																1,819
Other comprehensive income (loss), net of tax	(1,729)																										(1,729)
Cash dividends declared:
Common stock	(698)																(698)
Preferred stock					(29)	(22)	(19)	(9)	(12)	(9)											(29)	(22)	(19)	(9)	(12)	(9)
Shares acquired for treasury	(201)																												(201)
Impact of stock transactions under stock compensation plans, net	89														49														40
Ending balance at Sep. 30, 2023	16,544										2,051		2,116		3,733		22,747										(6,839)		(7,264)
Beginning balance at Jun. 30, 2023	17,809										2,051		2,116		3,708		22,366										(5,166)		(7,266)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	660																660
Other comprehensive income (loss), net of tax	(1,673)																										(1,673)
Cash dividends declared:
Common stock	(242)																(242)
Preferred stock					$ (13)	$ (7)	$ (7)	$ (3)	$ (4)	$ (3)											$ (13)	$ (7)	$ (7)	$ (3)	$ (4)	$ (3)
Impact of stock transactions under stock compensation plans, net	27														25														2
Ending balance at Sep. 30, 2023	$ 16,544										$ 2,051		$ 2,116		$ 3,733		$ 22,747										$ (6,839)		$ (7,264)

[1] Related to the adoption of ASU 2022-02 as of January 1, 2023. Refer to Note 3 for additional information.