Derivative Instruments - Impact on Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Gross derivative receivables	$ 574,004	$ 707,554
Net derivative receivables	70,711	79,630
Gross derivative payables	552,881	688,887
Net derivative payables	56,045	70,623
Interest rate
Derivatives, Fair Value [Line Items]
Gross derivative receivables	304,249	391,648
Net derivative receivables	26,046	35,725
Gross derivative payables	270,175	353,987
Net derivative payables	9,190	13,012
Credit
Derivatives, Fair Value [Line Items]
Gross derivative receivables	10,104	13,345
Net derivative receivables	948	680
Gross derivative payables	11,515	14,832
Net derivative payables	1,184	1,995
Foreign exchange
Derivatives, Fair Value [Line Items]
Gross derivative receivables	157,417	206,260
Net derivative receivables	14,507	15,781
Gross derivative payables	156,751	215,926
Net derivative payables	13,715	21,433
Equity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	73,104	74,798
Net derivative receivables	16,861	20,673
Gross derivative payables	84,557	81,413
Net derivative payables	21,100	25,898
Commodity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	29,130	21,503
Net derivative receivables	12,349	6,771
Gross derivative payables	29,883	22,729
Net derivative payables	10,856	8,285
Not designated as hedges
Derivatives, Fair Value [Line Items]
Gross derivative receivables	569,043	704,898
Gross derivative payables	547,083	685,295
Not designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Gross derivative receivables	303,469	390,817
Gross derivative payables	270,175	353,987
Not designated as hedges | Credit
Derivatives, Fair Value [Line Items]
Gross derivative receivables	10,104	13,345
Gross derivative payables	11,515	14,832
Not designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Gross derivative receivables	156,349	205,359
Gross derivative payables	155,369	214,229
Not designated as hedges | Equity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	73,104	74,798
Gross derivative payables	84,557	81,413
Not designated as hedges | Commodity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	26,017	20,579
Gross derivative payables	25,467	20,834
Designated as hedges
Derivatives, Fair Value [Line Items]
Gross derivative receivables	4,961	2,656
Gross derivative payables	5,798	3,592
Designated as hedges | Interest rate
Derivatives, Fair Value [Line Items]
Gross derivative receivables	780	831
Gross derivative payables	0	0
Designated as hedges | Credit
Derivatives, Fair Value [Line Items]
Gross derivative receivables	0	0
Gross derivative payables	0	0
Designated as hedges | Foreign exchange
Derivatives, Fair Value [Line Items]
Gross derivative receivables	1,068	901
Gross derivative payables	1,382	1,697
Designated as hedges | Equity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	0	0
Gross derivative payables	0	0
Designated as hedges | Commodity
Derivatives, Fair Value [Line Items]
Gross derivative receivables	3,113	924
Gross derivative payables	$ 4,416	$ 1,895