Investment Securities - Schedule of Gross Pre-Tax Unrealized Losses on Investment Securities (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	$ 27,972	$ 41,232
Available for sale, gross unrealized losses less than 12 months	686	422
Available for sale, fair value 12 months or longer	11,167	2,277
Available for sale, gross unrealized losses 12 months or longer	706	23
Available for sale, fair value total	39,139	43,509
Available for sale, gross unrealized losses total	1,392	445
Direct obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,995	14,749
Available for sale, gross unrealized losses less than 12 months	38	194
Available for sale, fair value 12 months or longer	5,206	1,624
Available for sale, gross unrealized losses 12 months or longer	269	2
Available for sale, fair value total	7,201	16,373
Available for sale, gross unrealized losses total	307	196
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	8,949	10,417
Available for sale, gross unrealized losses less than 12 months	180	80
Available for sale, fair value 12 months or longer	346	369
Available for sale, gross unrealized losses 12 months or longer	35	14
Available for sale, fair value total	9,295	10,786
Available for sale, gross unrealized losses total	215	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	10,944	25,166
Available for sale, gross unrealized losses less than 12 months	218	274
Available for sale, fair value 12 months or longer	5,552	1,993
Available for sale, gross unrealized losses 12 months or longer	304	16
Available for sale, fair value total	16,496	27,159
Available for sale, gross unrealized losses total	522	290
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,343	577
Available for sale, gross unrealized losses less than 12 months	14	3
Available for sale, fair value 12 months or longer	235	30
Available for sale, gross unrealized losses 12 months or longer	4	0
Available for sale, fair value total	1,578	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	1,361	1,021
Available for sale, gross unrealized losses less than 12 months	25	2
Available for sale, fair value 12 months or longer	245	127
Available for sale, gross unrealized losses 12 months or longer	6	0
Available for sale, fair value total	1,606	1,148
Available for sale, gross unrealized losses total	31	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	9,820	10,406
Available for sale, gross unrealized losses less than 12 months	271	97
Available for sale, fair value 12 months or longer	3,042	63
Available for sale, gross unrealized losses 12 months or longer	199	3
Available for sale, fair value total	12,862	10,469
Available for sale, gross unrealized losses total	470	100
Other
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	970	1,570
Available for sale, gross unrealized losses less than 12 months	51	31
Available for sale, fair value 12 months or longer	1,023	19
Available for sale, gross unrealized losses 12 months or longer	127	1
Available for sale, fair value total	1,993	1,589
Available for sale, gross unrealized losses total	178	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	13,494	13,574
Available for sale, gross unrealized losses less than 12 months	361	133
Available for sale, fair value 12 months or longer	4,545	239
Available for sale, gross unrealized losses 12 months or longer	336	4
Available for sale, fair value total	18,039	13,813
Available for sale, gross unrealized losses total	697	137
Student loans
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	84
Available for sale, gross unrealized losses less than 12 months	1
Available for sale, fair value 12 months or longer	6
Available for sale, gross unrealized losses 12 months or longer	0
Available for sale, fair value total	90
Available for sale, gross unrealized losses total	1
Collateralized loan obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,728	1,268
Available for sale, gross unrealized losses less than 12 months	40	2
Available for sale, fair value 12 months or longer	591	0
Available for sale, gross unrealized losses 12 months or longer	14	0
Available for sale, fair value total	2,319	1,268
Available for sale, gross unrealized losses total	54	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	215
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	215
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	88
Available for sale, gross unrealized losses less than 12 months	2
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	88
Available for sale, gross unrealized losses total	2
Total asset-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	2,115	1,268
Available for sale, gross unrealized losses less than 12 months	48	2
Available for sale, fair value 12 months or longer	597	0
Available for sale, gross unrealized losses 12 months or longer	14	0
Available for sale, fair value total	2,712	1,268
Available for sale, gross unrealized losses total	62	2
State and political subdivisions
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	860	10
Available for sale, gross unrealized losses less than 12 months	23	0
Available for sale, fair value 12 months or longer	42	45
Available for sale, gross unrealized losses 12 months or longer	5	3
Available for sale, fair value total	902	55
Available for sale, gross unrealized losses total	28	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	559	1,214
Available for sale, gross unrealized losses less than 12 months	36	13
Available for sale, fair value 12 months or longer	431	0
Available for sale, gross unrealized losses 12 months or longer	47	0
Available for sale, fair value total	990	1,214
Available for sale, gross unrealized losses total	$ 83	$ 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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