CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (unaudited) - USD ($) $ in Millions	Total	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	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	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 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	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	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, 2023	$ 19,172							$ (10)	$ 19,162	$ 2,051	$ 2,051	$ 2,116	$ 2,116	$ 3,757	$ 3,757	$ 22,997							$ (10)	$ 22,987	$ (4,487)	$ (4,487)	$ (7,262)	$ (7,262)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	520															520
Other comprehensive loss, net of tax	(401)																								(401)
Cash dividends declared:
Common stock	(243)															(243)
Preferred stock		$ (13)	$ (10)	$ (7)	$ (3)	$ (4)	$ (3)										$ (13)	$ (10)	$ (7)	$ (3)	$ (4)	$ (3)
Impact of stock transactions under stock compensation plans, net	20													(15)													35
Ending balance at Mar. 31, 2024	19,018									2,051		2,116		3,742		23,224									(4,888)		(7,227)
Beginning balance at Dec. 31, 2024	19,645									2,051		2,116		3,804		24,150									(4,636)		(7,840)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	515															515
Other comprehensive loss, net of tax	741																								741
Cash dividends declared:
Common stock	(251)															(251)
Preferred stock		$ (12)	$ (9)	$ (6)	$ (3)	$ (4)	$ (3)										$ (12)	$ (9)	$ (6)	$ (3)	$ (4)	$ (3)
Shares acquired for treasury	(226)																										(226)
Impact of stock transactions under stock compensation plans, net	16													(31)													47
Ending balance at Mar. 31, 2025	$ 20,403									$ 2,051		$ 2,116		$ 3,773		$ 24,377									$ (3,895)		$ (8,019)