Investment Securities - Schedule of Gross Pre-Tax Unrealized Losses on Investment Securities (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	$ 19,429	$ 41,232
Available for sale, gross unrealized losses less than 12 months	368	422
Available for sale, fair value 12 months or longer	18,093	2,277
Available for sale, gross unrealized losses 12 months or longer	924	23
Available for sale, fair value total	37,522	43,509
Available for sale, gross unrealized losses total	1,293	445
US Treasury and federal agencies, direct obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,337	14,749
Available for sale, gross unrealized losses less than 12 months	15	194
Available for sale, fair value 12 months or longer	5,745	1,624
Available for sale, gross unrealized losses 12 months or longer	246	2
Available for sale, fair value total	7,082	16,373
Available for sale, gross unrealized losses total	261	196
US Treasury and federal agencies, mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	5,524	10,417
Available for sale, gross unrealized losses less than 12 months	130	80
Available for sale, fair value 12 months or longer	2,815	369
Available for sale, gross unrealized losses 12 months or longer	130	14
Available for sale, fair value total	8,339	10,786
Available for sale, gross unrealized losses total	260	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	6,861	25,166
Available for sale, gross unrealized losses less than 12 months	145	274
Available for sale, fair value 12 months or longer	8,560	1,993
Available for sale, gross unrealized losses 12 months or longer	376	16
Available for sale, fair value total	15,421	27,159
Available for sale, gross unrealized losses total	521	290
Non-U.S. debt securities, mortgage-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,278	577
Available for sale, gross unrealized losses less than 12 months	15	3
Available for sale, fair value 12 months or longer	272	30
Available for sale, gross unrealized losses 12 months or longer	4	0
Available for sale, fair value total	1,550	607
Available for sale, gross unrealized losses total	19	3
Non-U.S. debt securities, asset-backed securities
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	859	1,021
Available for sale, gross unrealized losses less than 12 months	11	2
Available for sale, fair value 12 months or longer	765	127
Available for sale, gross unrealized losses 12 months or longer	16	0
Available for sale, fair value total	1,624	1,148
Available for sale, gross unrealized losses total	27	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	6,750	10,406
Available for sale, gross unrealized losses less than 12 months	108	97
Available for sale, fair value 12 months or longer	5,800	63
Available for sale, gross unrealized losses 12 months or longer	316	3
Available for sale, fair value total	12,550	10,469
Available for sale, gross unrealized losses total	424	100
Non-U.S. debt securities, other
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	771	1,570
Available for sale, gross unrealized losses less than 12 months	27	31
Available for sale, fair value 12 months or longer	1,233	19
Available for sale, gross unrealized losses 12 months or longer	137	1
Available for sale, fair value total	2,004	1,589
Available for sale, gross unrealized losses total	164	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	9,658	13,574
Available for sale, gross unrealized losses less than 12 months	161	133
Available for sale, fair value 12 months or longer	8,070	239
Available for sale, gross unrealized losses 12 months or longer	473	4
Available for sale, fair value total	17,728	13,813
Available for sale, gross unrealized losses total	634	137
Asset-backed securities, 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
Asset-backed securities, collateralized loan obligations
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	1,577	1,268
Available for sale, gross unrealized losses less than 12 months	27	2
Available for sale, fair value 12 months or longer	710	0
Available for sale, gross unrealized losses 12 months or longer	12	0
Available for sale, fair value total	2,287	1,268
Available for sale, gross unrealized losses total	39	2
Asset-backed securities, non-agency CMBS and RMBS
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	193
Available for sale, gross unrealized losses less than 12 months	6
Available for sale, fair value 12 months or longer	3
Available for sale, gross unrealized losses 12 months or longer	0
Available for sale, fair value total	196
Available for sale, gross unrealized losses total	6
Asset-backed securities, 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	1,947	1,268
Available for sale, gross unrealized losses less than 12 months	36	2
Available for sale, fair value 12 months or longer	713	0
Available for sale, gross unrealized losses 12 months or longer	12	0
Available for sale, fair value total	2,660	1,268
Available for sale, gross unrealized losses total	48	2
State and political subdivisions
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, fair value less than 12 months	669	10
Available for sale, gross unrealized losses less than 12 months	12	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	711	55
Available for sale, gross unrealized losses total	17	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	294	1,214
Available for sale, gross unrealized losses less than 12 months	15	13
Available for sale, fair value 12 months or longer	708	0
Available for sale, gross unrealized losses 12 months or longer	58	0
Available for sale, fair value total	1,002	1,214
Available for sale, gross unrealized losses total	$ 73	$ 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 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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