Consolidated Statements of Cash Flows - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net income		$ 29,131	$ 36,431	$ 32,474
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Provision for credit losses		17,480	5,585	4,871
Depreciation and amortization		8,614	8,368	7,791
Deferred tax expense		(3,981)	949	1,721
Other		1,649	1,996	2,717
Originations and purchases of loans held-for-sale	[1]	(166,504)	(169,289)	(172,728)
Proceeds from sales, securitizations and paydowns of loans held-for-sale	[1]	175,490	171,415	163,747
Net change in:
Trading assets	[1]	(148,749)	6,551	(35,067)
Securities borrowed		(20,734)	(27,631)	(6,861)
Accrued interest and accounts receivable		(18,012)	(78)	(5,849)
Other assets	[1]	(42,434)	(17,570)	(8,779)
Trading liabilities		77,198	(14,516)	18,290
Accounts payable and other liabilities		7,827	(352)	14,630
Other operating adjustments	[1]	3,115	2,233	(1,343)
Net cash provided by/(used in) operating activities		(79,910)	4,092	15,614
Net change in:
Federal funds sold and securities purchased under resale agreements		(47,115)	72,396	(123,201)
Held-to-maturity securities:
Proceeds from paydowns and maturities		21,360	3,423	2,945
Purchases		(12,400)	(13,427)	(9,368)
Available-for-sale securities:
Proceeds from paydowns and maturities		57,675	52,200	37,401
Proceeds from sales		149,758	70,181	46,067
Purchases		(397,145)	(242,149)	(95,091)
Proceeds from sales and securitizations of loans held-for-investment		23,559	62,095	29,826
Other changes in loans, net	[1]	(50,263)	(51,743)	(83,013)
All other investing activities, net		(7,341)	(5,035)	(4,986)
Net cash (used in) investing activities		(261,912)	(52,059)	(199,420)
Net change in:
Deposits		602,765	101,002	26,728
Federal funds purchased and securities loaned or sold under repurchase agreements		31,528	1,347	23,415
Short-term borrowings			(28,561)
Short-term borrowings		4,438		18,476
Beneficial interests issued by consolidated VIEs		1,347	4,289	1,712
Proceeds from long-term borrowings		78,686	61,085	71,662
Payments of long-term borrowings		(105,055)	(69,610)	(76,313)
Proceeds from issuance of preferred stock		4,500	5,000	1,696
Redemption of preferred stock		(1,430)	(4,075)	(1,696)
Treasury stock repurchased		(6,517)	(24,001)	(19,983)
Dividends paid		(12,690)	(12,343)	(10,109)
All other financing activities, net		(927)	(1,146)	(1,430)
Net cash provided by financing activities		596,645	32,987	34,158
Effect of exchange rate changes on cash and due from banks and deposits with banks		9,155	(182)	(2,863)
Net increase/(decrease) in cash and due from banks and deposits with banks		263,978	(15,162)	(152,511)
Cash and due from banks and deposits with banks at the beginning of the period		263,631	278,793	431,304
Cash and due from banks and deposits with banks at the end of the period		527,609	263,631	278,793
Cash interest paid		13,077	29,918	21,152
Cash income taxes paid, net		$ 7,661	$ 5,624	$ 3,542

[1] In the third quarter of 2020, the Firm reclassified certain fair value option elected lending-related positions from trading assets to loans and other assets. Prior-period amounts have been revised to conform with the current presentation.