Derivative Instruments - Derivatives Netting (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	$ 583,913	$ 681,647
Amounts netted on the Consolidated balance sheets	(536,598)	(627,924)
Net derivative receivables	47,315	53,723
Derivative receivables where an appropriate legal opinion has not been either sought or obtained	25,804	25,907
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	609,717	707,554
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	73,119	79,630
Collateral not nettable on the Consolidated balance sheets	(13,958)	(14,806)
Net amounts	59,161	64,824
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	562,602	665,950
Amounts netted on the Consolidated balance sheets	(522,257)	(618,264)
Net derivative payables	40,345	47,686
Derivative payables where an appropriate legal opinion has not been either sought or obtained	20,095	22,937
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	582,697	688,887
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	60,440	70,623
Collateral not nettable on the Consolidated balance sheets	(9,193)	(11,964)
Net amounts	51,247	58,659
Net cash collateral receivables	74,600	88,000
Net cash collateral payables	60,200	78,400
Interest rate contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	306,148	385,950
Amounts netted on the Consolidated balance sheets	(283,073)	(355,765)
Net derivative receivables	23,075	30,185
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	311,621	391,490
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	28,548	35,725
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	277,620	351,922
Amounts netted on the Consolidated balance sheets	(268,442)	(340,615)
Net derivative payables	9,178	11,307
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	279,186	353,627
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	10,744	13,012
Interest rate contracts | Over-the-counter (“OTC”)
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	288,187	367,056
Amounts netted on the Consolidated balance sheets	(265,270)	(337,451)
Net derivative receivables	22,917	29,605
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	257,384	331,854
Amounts netted on the Consolidated balance sheets	(249,248)	(320,780)
Net derivative payables	8,136	11,074
Interest rate contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	17,627	18,340
Amounts netted on the Consolidated balance sheets	(17,498)	(17,919)
Net derivative receivables	129	421
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	19,914	19,710
Amounts netted on the Consolidated balance sheets	(18,884)	(19,494)
Net derivative payables	1,030	216
Interest rate contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	334	554
Amounts netted on the Consolidated balance sheets	(305)	(395)
Net derivative receivables	29	159
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	322	358
Amounts netted on the Consolidated balance sheets	(310)	(341)
Net derivative payables	12	17
Net credit derivatives
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	13,987	13,378
Amounts netted on the Consolidated balance sheets	(13,164)	(12,823)
Net derivative receivables	823	555
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	14,212	13,503
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	1,048	680
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	14,162	14,746
Amounts netted on the Consolidated balance sheets	(12,704)	(13,197)
Net derivative payables	1,458	1,549
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	14,602	15,192
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	1,898	1,995
Net credit derivatives | Over-the-counter (“OTC”)
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	9,229	9,052
Amounts netted on the Consolidated balance sheets	(8,460)	(8,514)
Net derivative receivables	769	538
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	9,841	10,671
Amounts netted on the Consolidated balance sheets	(8,412)	(9,141)
Net derivative payables	1,429	1,530
Net credit derivatives | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	4,758	4,326
Amounts netted on the Consolidated balance sheets	(4,704)	(4,309)
Net derivative receivables	54	17
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	4,321	4,075
Amounts netted on the Consolidated balance sheets	(4,292)	(4,056)
Net derivative payables	29	19
Foreign exchange contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	182,610	202,218
Amounts netted on the Consolidated balance sheets	(171,515)	(190,479)
Net derivative receivables	11,095	11,739
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	186,627	206,260
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	15,112	15,781
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	181,441	211,673
Amounts netted on the Consolidated balance sheets	(168,468)	(194,493)
Net derivative payables	12,973	17,180
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	185,506	215,926
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	17,038	21,433
Foreign exchange contracts | Over-the-counter (“OTC”)
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	181,701	201,349
Amounts netted on the Consolidated balance sheets	(170,672)	(189,655)
Net derivative receivables	11,029	11,694
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	180,571	210,803
Amounts netted on the Consolidated balance sheets	(167,627)	(193,672)
Net derivative payables	12,944	17,131
Foreign exchange contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	891	834
Amounts netted on the Consolidated balance sheets	(841)	(819)
Net derivative receivables	50	15
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	857	836
Amounts netted on the Consolidated balance sheets	(841)	(819)
Net derivative payables	16	17
Foreign exchange contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	18	35
Amounts netted on the Consolidated balance sheets	(2)	(5)
Net derivative receivables	16	30
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	13	34
Amounts netted on the Consolidated balance sheets	0	(2)
Net derivative payables	13	32
Equity contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	61,029	62,324
Amounts netted on the Consolidated balance sheets	(53,825)	(54,125)
Net derivative receivables	7,204	8,199
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	73,578	74,798
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	19,753	20,673
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	70,417	69,821
Amounts netted on the Consolidated balance sheets	(57,143)	(55,515)
Net derivative payables	13,274	14,306
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	79,543	81,413
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	22,400	25,898
Equity contracts | Over-the-counter (“OTC”)
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	30,396	34,030
Amounts netted on the Consolidated balance sheets	(23,963)	(27,374)
Net derivative receivables	6,433	6,656
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	33,285	35,330
Amounts netted on the Consolidated balance sheets	(27,282)	(28,763)
Net derivative payables	6,003	6,567
Equity contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	30,633	28,294
Amounts netted on the Consolidated balance sheets	(29,862)	(26,751)
Net derivative receivables	771	1,543
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	37,132	34,491
Amounts netted on the Consolidated balance sheets	(29,861)	(26,752)
Net derivative payables	7,271	7,739
Commodity contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	20,139	17,777
Amounts netted on the Consolidated balance sheets	(15,021)	(14,732)
Net derivative receivables	5,118	3,045
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivative receivables	23,679	21,503
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	8,658	6,771
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	18,962	17,788
Amounts netted on the Consolidated balance sheets	(15,500)	(14,444)
Net derivative payables	3,462	3,344
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	23,860	22,729
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	8,360	8,285
Commodity contracts | Over-the-counter (“OTC”)
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	11,725	10,924
Amounts netted on the Consolidated balance sheets	(6,789)	(7,901)
Net derivative receivables	4,936	3,023
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	10,338	10,365
Amounts netted on the Consolidated balance sheets	(7,253)	(7,544)
Net derivative payables	3,085	2,821
Commodity contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	36	20
Amounts netted on the Consolidated balance sheets	(36)	(20)
Net derivative receivables	0	0
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	53	32
Amounts netted on the Consolidated balance sheets	(53)	(32)
Net derivative payables	0	0
Commodity contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	8,378	6,833
Amounts netted on the Consolidated balance sheets	(8,196)	(6,811)
Net derivative receivables	182	22
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	8,571	7,391
Amounts netted on the Consolidated balance sheets	(8,194)	(6,868)
Net derivative payables	$ 377	$ 523