Derivative Instruments - Derivatives Netting (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	$ 681,647	$ 516,083
Amounts netted on the Consolidated balance sheets	(627,924)	(479,860)
Net derivative receivables	53,723	36,223
Derivative receivables where an appropriate legal opinion has not been either sought or obtained	25,907	13,543
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	707,554	529,626
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	79,630	49,766
Collateral not nettable on the Consolidated balance sheets, Net derivative receivables	(14,806)	(13,052)
Net amounts, Net derivative receivables	64,824	36,714
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	665,950	497,977
Amounts netted on the Consolidated balance sheets	(618,264)	(468,420)
Net derivative payables	47,686	29,557
Derivative payables where an appropriate legal opinion has not been either sought or obtained	22,937	14,151
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	688,887	512,128
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	70,623	43,708
Collateral not nettable on the Consolidated balance sheets, Net derivative payables	(11,964)	(6,960)
Net amounts, Net derivative payables	58,659	36,748
Net cash collateral receivables	88,000	65,900
Netted cash collateral payables	78,400	54,400
Interest rate contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	385,950	308,994
Amounts netted on the Consolidated balance sheets	(355,765)	(285,873)
Net derivative receivables	30,185	23,121
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	391,490	313,294
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	35,725	27,421
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	351,922	277,893
Amounts netted on the Consolidated balance sheets	(340,615)	(270,670)
Net derivative payables	11,307	7,223
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	353,627	279,273
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	13,012	8,603
Interest rate contracts | OTC
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	367,056	299,205
Amounts netted on the Consolidated balance sheets	(337,451)	(276,255)
Net derivative receivables	29,605	22,950
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	331,854	267,311
Amounts netted on the Consolidated balance sheets	(320,780)	(260,229)
Net derivative payables	11,074	7,082
Interest rate contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	18,340	9,442
Amounts netted on the Consolidated balance sheets	(17,919)	(9,360)
Net derivative receivables	421	82
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	19,710	10,217
Amounts netted on the Consolidated balance sheets	(19,494)	(10,138)
Net derivative payables	216	79
Interest rate contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	554	347
Amounts netted on the Consolidated balance sheets	(395)	(258)
Net derivative receivables	159	89
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	358	365
Amounts netted on the Consolidated balance sheets	(341)	(303)
Net derivative payables	17	62
Credit contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	13,378	14,607
Amounts netted on the Consolidated balance sheets	(12,823)	(14,175)
Net derivative receivables	555	432
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	13,503	14,876
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	680	701
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	14,746	14,960
Amounts netted on the Consolidated balance sheets	(13,197)	(13,469)
Net derivative payables	1,549	1,491
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	15,192	15,121
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	1,995	1,652
Credit contracts | OTC
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	9,052	10,743
Amounts netted on the Consolidated balance sheets	(8,514)	(10,317)
Net derivative receivables	538	426
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	10,671	11,570
Amounts netted on the Consolidated balance sheets	(9,141)	(10,080)
Net derivative payables	1,530	1,490
Credit contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	4,326	3,864
Amounts netted on the Consolidated balance sheets	(4,309)	(3,858)
Net derivative receivables	17	6
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	4,075	3,390
Amounts netted on the Consolidated balance sheets	(4,056)	(3,389)
Net derivative payables	19	1
Foreign exchange contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	202,218	136,447
Amounts netted on the Consolidated balance sheets	(190,479)	(129,482)
Net derivative receivables	11,739	6,965
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	206,260	138,487
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	15,781	9,005
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	211,673	142,558
Amounts netted on the Consolidated balance sheets	(194,493)	(131,950)
Net derivative payables	17,180	10,608
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	215,926	145,108
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	21,433	13,158
Foreign exchange contracts | OTC
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	201,349	136,252
Amounts netted on the Consolidated balance sheets	(189,655)	(129,324)
Net derivative receivables	11,694	6,928
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	210,803	142,360
Amounts netted on the Consolidated balance sheets	(193,672)	(131,792)
Net derivative payables	17,131	10,568
Foreign exchange contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	834	185
Amounts netted on the Consolidated balance sheets	(819)	(152)
Net derivative receivables	15	33
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	836	186
Amounts netted on the Consolidated balance sheets	(819)	(152)
Net derivative payables	17	34
Foreign exchange contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	35	10
Amounts netted on the Consolidated balance sheets	(5)	(6)
Net derivative receivables	30	4
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	34	12
Amounts netted on the Consolidated balance sheets	(2)	(6)
Net derivative payables	32	6
Equity contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	62,324	42,760
Amounts netted on the Consolidated balance sheets	(54,125)	(39,250)
Net derivative receivables	8,199	3,510
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	74,798	45,727
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	20,673	6,477
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	69,821	47,810
Amounts netted on the Consolidated balance sheets	(55,515)	(40,204)
Net derivative payables	14,306	7,606
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	81,413	52,741
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	25,898	12,537
Equity contracts | OTC
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	34,030	23,106
Amounts netted on the Consolidated balance sheets	(27,374)	(20,820)
Net derivative receivables	6,656	2,286
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	35,330	27,594
Amounts netted on the Consolidated balance sheets	(28,763)	(21,778)
Net derivative payables	6,567	5,816
Equity contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	28,294	19,654
Amounts netted on the Consolidated balance sheets	(26,751)	(18,430)
Net derivative receivables	1,543	1,224
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	34,491	20,216
Amounts netted on the Consolidated balance sheets	(26,752)	(18,426)
Net derivative payables	7,739	1,790
Commodity contracts
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	17,777	13,275
Amounts netted on the Consolidated balance sheets	(14,732)	(11,080)
Net derivative receivables	3,045	2,195
Total derivative receivables recognized on the Consolidated balance sheets, Gross derivate receivables	21,503	17,242
Total derivative receivables recognized on the Consolidated balance sheets, Net derivative receivables	6,771	6,162
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	17,788	14,756
Amounts netted on the Consolidated balance sheets	(14,444)	(12,127)
Net derivative payables	3,344	2,629
Total derivative payables recognized on the Consolidated balance sheets, Gross derivative payables	22,729	19,885
Total derivative payables recognized on the Consolidated balance sheets, Net derivative payables	8,285	7,758
Commodity contracts | OTC
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	10,924	7,093
Amounts netted on the Consolidated balance sheets	(7,901)	(5,149)
Net derivative receivables	3,023	1,944
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	10,365	8,714
Amounts netted on the Consolidated balance sheets	(7,544)	(6,235)
Net derivative payables	2,821	2,479
Commodity contracts | OTC–cleared
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	20	28
Amounts netted on the Consolidated balance sheets	(20)	(28)
Net derivative receivables	0	0
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	32	30
Amounts netted on the Consolidated balance sheets	(32)	(30)
Net derivative payables	0	0
Commodity contracts | Exchange-traded
Gross and Net Derivative Receivables by Contract and Settlement Type:
Gross derivative receivables	6,833	6,154
Amounts netted on the Consolidated balance sheets	(6,811)	(5,903)
Net derivative receivables	22	251
Gross and Net Derivative Payables by Contract and Settlement Type:
Gross derivative payables	7,391	6,012
Amounts netted on the Consolidated balance sheets	(6,868)	(5,862)
Net derivative payables	$ 523	$ 150