Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred stock	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income/(loss)	Treasury stock, at cost
Beginning balance at Dec. 31, 2020		$ 30,063	$ 4,105	$ 88,394	$ 236,990	$ 7,986	$ (88,184)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		5,350
Redemption		(2,575)
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				(134)
Other				(66)
Net income	$ 26,248				26,248
Dividends declared:
Preferred stock					(772)
Common stock ($1.00 and $0.90 per share and $2.00 and $1.80 per share, respectively)					(5,483)
Other comprehensive income/(loss), after-tax	(5,416)					(5,416)
Repurchase							(11,200)
Reissuance							1,080
Ending balance at Jun. 30, 2021	286,386	32,838	4,105	88,194	256,983	2,570	(98,304)
Beginning balance at Mar. 31, 2021		31,563	4,105	88,005	248,151	1,041	(92,151)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		3,850
Redemption		(2,575)
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				229
Other				(40)
Net income	11,948				11,948
Dividends declared:
Preferred stock					(393)
Common stock ($1.00 and $0.90 per share and $2.00 and $1.80 per share, respectively)					(2,723)
Other comprehensive income/(loss), after-tax	1,529					1,529
Repurchase							(6,201)
Reissuance							48
Ending balance at Jun. 30, 2021	286,386	32,838	4,105	88,194	256,983	2,570	(98,304)
Beginning balance at Dec. 31, 2021	294,127	34,838	4,105	88,415	272,268	(84)	(105,415)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance		0
Redemption		(2,000)
Shares issued and commitments to issue common stock for employee share-based compensation awards, and related tax effects				199
Other				0
Net income	16,931				16,931
Dividends declared:
Preferred stock					(807)
Common stock ($1.00 and $0.90 per share and $2.00 and $1.80 per share, respectively)					(5,947)
Other comprehensive income/(loss), after-tax	(14,285)					(14,285)
Repurchase							(3,122)
Reissuance							1,047
Ending balance at Jun. 30, 2022	286,143	32,838	4,105	88,614	282,445	(14,369)	(107,490)
Beginning balance at Mar. 31, 2022		32,838	4,105	88,260	277,177	(9,567)	(106,914)
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				354
Other				0
Net income	8,649				8,649
Dividends declared:
Preferred stock					(410)
Common stock ($1.00 and $0.90 per share and $2.00 and $1.80 per share, respectively)					(2,971)
Other comprehensive income/(loss), after-tax	(4,802)					(4,802)
Repurchase							(622)
Reissuance							46
Ending balance at Jun. 30, 2022	$ 286,143	$ 32,838	$ 4,105	$ 88,614	$ 282,445	$ (14,369)	$ (107,490)