Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net income		$ 14,300	$ 2,865
Adjustments to reconcile net income to net cash used in operating activities:
Provision for credit losses		(4,156)	8,285
Depreciation and amortization		2,070	2,197
Deferred tax (benefit)/expense	[1]	998	(1,235)
Other		890	411
Originations and purchases of loans held-for-sale		(85,457)	(47,352)
Proceeds from sales, securitizations and paydowns of loans held-for-sale		75,547	52,345
Net change in:
Trading assets		(34,262)	(167,827)
Securities borrowed		(18,951)	145
Accrued interest and accounts receivable		(24,323)	(49,323)
Other assets	[1]	7,131	(61,897)
Trading liabilities		(7)	97,078
Accounts payable and other liabilities	[1]	23,559	45,020
Other operating adjustments		(1,211)	(801)
Net cash (used in) operating activities		(43,872)	(120,089)
Net change in:
Federal funds sold and securities purchased under resale agreements		23,791	1,120
Held-to-maturity securities:
Proceeds from paydowns and maturities		14,700	2,599
Purchases		(31,348)	(205)
Available-for-sale securities:
Proceeds from paydowns and maturities		14,096	12,420
Proceeds from sales		80,823	50,990
Purchases		(95,958)	(131,605)
Proceeds from sales and securitizations of loans held-for-investment		6,619	7,564
Other changes in loans, net		3,321	(65,608)
Net purchases of assets pursuant to nonrecourse advances provided by the FRBB under the MMLF		0	(11,985)
All other investing activities, net		(653)	(1,123)
Net cash provided by/(used in) investing activities		15,391	(135,833)
Net change in:
Deposits		120,501	297,976
Federal funds purchased and securities loaned or sold under repurchase agreements		88,844	49,273
Short-term borrowings		9,387	12,455
Beneficial interests issued by consolidated VIEs		(1,439)	1,613
Proceeds from long-term borrowings		24,162	34,851
Payments of long-term borrowings		(14,983)	(29,057)
Proceeds from issuance of preferred stock		1,500	4,500
Redemption of preferred stock		0	(1,430)
Treasury stock repurchased		(4,806)	(6,517)
Dividends paid		(3,193)	(3,188)
All other financing activities, net		(1,062)	1,829
Net cash provided by financing activities		218,911	362,305
Effect of exchange rate changes on cash and due from banks and deposits with banks		(6,967)	(2,480)
Net increase in cash and due from banks and deposits with banks		183,463	103,903
Cash and due from banks and deposits with banks at the beginning of the period		527,609	263,631
Cash and due from banks and deposits with banks at the end of the period		711,072	367,534
Cash interest paid		1,127	4,374
Cash income taxes paid, net		$ 640	$ 763

[1] Prior-period amounts have been revised to conform with the current presentation. Refer to Note 1 for further information.