Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Preferred stock	Common stock	Additional paid-in capital	Retained earnings	Retained earnings Cumulative effect of change in accounting principles	Accumulated other comprehensive income/(loss)	Treasury stock, at cost
Beginning balance at Dec. 31, 2021		$ 34,838	$ 4,105	$ 88,415	$ 272,268		$ (84)	$ (105,415)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		0
Redemption		(7,434)
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				629
Other				0
Net income	$ 37,676				37,676
Preferred stock dividends					(1,595)
Common stock dividends ($4.80, $4.10 and $4.00 per share for 2024, 2023 and 2022, respectively)					(11,893)
Other comprehensive income/(loss), after-tax	(17,257)						(17,257)
Repurchase			(3,122)					(3,122)
Reissuance								1,201
Ending balance at Dec. 31, 2022	292,332	27,404	4,105	89,044	296,456	$ 449	(17,341)	(107,336)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		0
Redemption		0
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				1,084
Other				0
Net income	49,552				49,552
Preferred stock dividends					(1,501)
Common stock dividends ($4.80, $4.10 and $4.00 per share for 2024, 2023 and 2022, respectively)					(12,055)
Other comprehensive income/(loss), after-tax	6,898						6,898
Repurchase			(9,898)					(9,980)
Reissuance								1,099
Ending balance at Dec. 31, 2023	327,878	27,404	4,105	90,128	332,901	$ (161)	(10,443)	(116,217)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		2,496
Redemption		(9,850)
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				768
Other				15
Net income	58,471				58,471
Preferred stock dividends					(1,259)
Common stock dividends ($4.80, $4.10 and $4.00 per share for 2024, 2023 and 2022, respectively)					(13,786)
Other comprehensive income/(loss), after-tax	(2,013)						(2,013)
Repurchase			(18,841)					(19,007)
Reissuance								1,206
Ending balance at Dec. 31, 2024	$ 344,758	$ 20,050	$ 4,105	$ 90,911	$ 376,166		$ (12,456)	$ (134,018)