Investment Securities - Schedule of Gross Pre-Tax Unrealized Losses on Investment Securities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	$ 10,491	$ 19,429
Available for sale, gross unrealized losses less than 12 months	95	369
Available for sale, fair value 12 months or longer	26,938	18,093
Available for sale, gross unrealized losses 12 months or longer	942	924
Available for sale, fair value total	37,429	37,522
Available for sale, gross unrealized losses total	1,037	1,293
Direct obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	127	1,337
Available for sale, gross unrealized losses less than 12 months	0	15
Available for sale, fair value 12 months or longer	6,536	5,745
Available for sale, gross unrealized losses 12 months or longer	218	246
Available for sale, fair value total	6,663	7,082
Available for sale, gross unrealized losses total	218	261
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	3,682	5,524
Available for sale, gross unrealized losses less than 12 months	41	130
Available for sale, fair value 12 months or longer	4,859	2,815
Available for sale, gross unrealized losses 12 months or longer	128	130
Available for sale, fair value total	8,541	8,339
Available for sale, gross unrealized losses total	169	260
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	3,809	6,861
Available for sale, gross unrealized losses less than 12 months	41	145
Available for sale, fair value 12 months or longer	11,395	8,560
Available for sale, gross unrealized losses 12 months or longer	346	376
Available for sale, fair value total	15,204	15,421
Available for sale, gross unrealized losses total	387	521
Mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	394	1,278
Available for sale, gross unrealized losses less than 12 months	2	15
Available for sale, fair value 12 months or longer	965	272
Available for sale, gross unrealized losses 12 months or longer	12	4
Available for sale, fair value total	1,359	1,550
Available for sale, gross unrealized losses total	14	19
Asset-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	276	859
Available for sale, gross unrealized losses less than 12 months	1	11
Available for sale, fair value 12 months or longer	1,275	765
Available for sale, gross unrealized losses 12 months or longer	23	16
Available for sale, fair value total	1,551	1,624
Available for sale, gross unrealized losses total	24	27
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	4,738	6,750
Available for sale, gross unrealized losses less than 12 months	29	108
Available for sale, fair value 12 months or longer	8,539	5,800
Available for sale, gross unrealized losses 12 months or longer	329	316
Available for sale, fair value total	13,277	12,550
Available for sale, gross unrealized losses total	358	424
Other
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	440	771
Available for sale, gross unrealized losses less than 12 months	7	27
Available for sale, fair value 12 months or longer	1,657	1,233
Available for sale, gross unrealized losses 12 months or longer	134	137
Available for sale, fair value total	2,097	2,004
Available for sale, gross unrealized losses total	141	164
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	5,848	9,658
Available for sale, gross unrealized losses less than 12 months	39	161
Available for sale, fair value 12 months or longer	12,436	8,070
Available for sale, gross unrealized losses 12 months or longer	498	473
Available for sale, fair value total	18,284	17,728
Available for sale, gross unrealized losses total	537	634
Student loans
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
Collateralized loan obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	426	1,577
Available for sale, gross unrealized losses less than 12 months	5	27
Available for sale, fair value 12 months or longer	1,851	710
Available for sale, gross unrealized losses 12 months or longer	26	12
Available for sale, fair value total	2,277	2,287
Available for sale, gross unrealized losses total	31	39
Non-agency CMBS and RMBS
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	143	193
Available for sale, gross unrealized losses less than 12 months	3	6
Available for sale, fair value 12 months or longer	96	3
Available for sale, gross unrealized losses 12 months or longer	3	0
Available for sale, fair value total	239	196
Available for sale, gross unrealized losses total	6	6
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	569	1,947
Available for sale, gross unrealized losses less than 12 months	8	36
Available for sale, fair value 12 months or longer	1,947	713
Available for sale, gross unrealized losses 12 months or longer	29	12
Available for sale, fair value total	2,516	2,660
Available for sale, gross unrealized losses total	37	48
State and political subdivisions
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	199	669
Available for sale, gross unrealized losses less than 12 months	3	12
Available for sale, fair value 12 months or longer	241	42
Available for sale, gross unrealized losses 12 months or longer	9	5
Available for sale, fair value total	440	711
Available for sale, gross unrealized losses total	12	17
Other U.S. debt securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	66	294
Available for sale, gross unrealized losses less than 12 months	4	15
Available for sale, fair value 12 months or longer	919	708
Available for sale, gross unrealized losses 12 months or longer	60	58
Available for sale, fair value total	985	1,002
Available for sale, gross unrealized losses total	$ 64	$ 73

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 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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