Investment Securities - Schedule of Gross Pre-Tax Unrealized Losses on Investment Securities (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	$ 37,636	$ 41,232
Available for sale, gross unrealized losses less than 12 months	929	422
Available for sale, fair value 12 months or longer	5,368	2,277
Available for sale, gross unrealized losses 12 months or longer	233	23
Available for sale, fair value total	43,004	43,509
Available for sale, gross unrealized losses total	1,162	445
Direct obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	6,778	14,749
Available for sale, gross unrealized losses less than 12 months	283	194
Available for sale, fair value 12 months or longer	2,062	1,624
Available for sale, gross unrealized losses 12 months or longer	38	2
Available for sale, fair value total	8,840	16,373
Available for sale, gross unrealized losses total	321	196
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	9,768	10,417
Available for sale, gross unrealized losses less than 12 months	119	80
Available for sale, fair value 12 months or longer	278	369
Available for sale, gross unrealized losses 12 months or longer	20	14
Available for sale, fair value total	10,046	10,786
Available for sale, gross unrealized losses total	139	94
Total U.S. Treasury and federal agencies
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	16,546	25,166
Available for sale, gross unrealized losses less than 12 months	402	274
Available for sale, fair value 12 months or longer	2,340	1,993
Available for sale, gross unrealized losses 12 months or longer	58	16
Available for sale, fair value total	18,886	27,159
Available for sale, gross unrealized losses total	460	290
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,783	577
Available for sale, gross unrealized losses less than 12 months	18	3
Available for sale, fair value 12 months or longer	41	30
Available for sale, gross unrealized losses 12 months or longer	0	0
Available for sale, fair value total	1,824	607
Available for sale, gross unrealized losses total	18	3
Asset-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,637	1,021
Available for sale, gross unrealized losses less than 12 months	23	2
Available for sale, fair value 12 months or longer	166	127
Available for sale, gross unrealized losses 12 months or longer	2	0
Available for sale, fair value total	1,803	1,148
Available for sale, gross unrealized losses total	25	2
Non-U.S. sovereign, supranational and non-U.S. agency
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	12,529	10,406
Available for sale, gross unrealized losses less than 12 months	301	97
Available for sale, fair value 12 months or longer	1,454	63
Available for sale, gross unrealized losses 12 months or longer	73	3
Available for sale, fair value total	13,983	10,469
Available for sale, gross unrealized losses total	374	100
Other
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,423	1,570
Available for sale, gross unrealized losses less than 12 months	87	31
Available for sale, fair value 12 months or longer	637	19
Available for sale, gross unrealized losses 12 months or longer	67	1
Available for sale, fair value total	2,060	1,589
Available for sale, gross unrealized losses total	154	32
Total non-U.S. debt securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	17,372	13,574
Available for sale, gross unrealized losses less than 12 months	429	133
Available for sale, fair value 12 months or longer	2,298	239
Available for sale, gross unrealized losses 12 months or longer	142	4
Available for sale, fair value total	19,670	13,813
Available for sale, gross unrealized losses total	571	137
Student loans
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	102
Available for sale, gross unrealized losses less than 12 months	2
Available for sale, fair value 12 months or longer	16
Available for sale, gross unrealized losses 12 months or longer	0
Available for sale, fair value total	118
Available for sale, gross unrealized losses total	2
Collateralized loan obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,902	1,268
Available for sale, gross unrealized losses less than 12 months	36	2
Available for sale, fair value 12 months or longer	433	0
Available for sale, gross unrealized losses 12 months or longer	7	0
Available for sale, fair value total	2,335	1,268
Available for sale, gross unrealized losses total	43	2
Non-agency CMBS and RMBS
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	195
Available for sale, gross unrealized losses less than 12 months	5
Available for sale, fair value 12 months or longer	0
Available for sale, gross unrealized losses 12 months or longer	0
Available for sale, fair value total	195
Available for sale, gross unrealized losses total	5
Other
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	89
Available for sale, gross unrealized losses less than 12 months	1
Available for sale, fair value 12 months or longer	0
Available for sale, gross unrealized losses 12 months or longer	0
Available for sale, fair value total	89
Available for sale, gross unrealized losses total	1
Total asset-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	2,288	1,268
Available for sale, gross unrealized losses less than 12 months	44	2
Available for sale, fair value 12 months or longer	449	0
Available for sale, gross unrealized losses 12 months or longer	7	0
Available for sale, fair value total	2,737	1,268
Available for sale, gross unrealized losses total	51	2
State and political subdivisions
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	667	10
Available for sale, gross unrealized losses less than 12 months	6	0
Available for sale, fair value 12 months or longer	43	45
Available for sale, gross unrealized losses 12 months or longer	4	3
Available for sale, fair value total	710	55
Available for sale, gross unrealized losses total	10	3
Other U.S. debt securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	763	1,214
Available for sale, gross unrealized losses less than 12 months	48	13
Available for sale, fair value 12 months or longer	238	0
Available for sale, gross unrealized losses 12 months or longer	22	0
Available for sale, fair value total	1,001	1,214
Available for sale, gross unrealized losses total	$ 70	$ 13

Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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