INVESTMENTS - Debt Securities Held-to-Maturity (Details) - USD ($) $ in Millions	1 Months Ended
Jan. 31, 2023	Jun. 30, 2024	Dec. 31, 2023
Held-to-maturity debt securities
Amortized cost, net		$ 251,125	$ 254,247
Gross unrealized gains		106	91
Gross unrealized losses		20,948	19,337
Fair value		230,283	235,001
Allowance for credit losses on HTM debt securities		99	95
Transfer of securities from HTM to AFS, unrealized gain	$ 100
Mortgage-backed securities
Held-to-maturity debt securities
Amortized cost, net		77,587	81,033
Gross unrealized gains		10	9
Gross unrealized losses		10,586	8,759
Fair value		67,011	72,283
U.S. government-sponsored agency guaranteed
Held-to-maturity debt securities
Amortized cost, net		76,208	79,689
Gross unrealized gains		8	7
Gross unrealized losses		10,454	8,603
Fair value		65,762	71,093
Mortgage-backed securities - Non-U.S. residential
Held-to-maturity debt securities
Amortized cost, net		145	198
Gross unrealized gains		0	0
Gross unrealized losses		0	0
Fair value		145	198
Commercial Mortgage-Backed Securities
Held-to-maturity debt securities
Amortized cost, net		1,234	1,146
Gross unrealized gains		2	2
Gross unrealized losses		132	156
Fair value		1,104	992
U.S. treasury securities
Held-to-maturity debt securities
Amortized cost, net		131,507	131,776
Gross unrealized gains		0	0
Gross unrealized losses		9,617	9,908
Fair value		121,890	121,868
State and municipal
Held-to-maturity debt securities
Amortized cost, net		8,999	9,182
Gross unrealized gains		31	73
Gross unrealized losses		651	477
Fair value		8,379	8,778
Foreign government
Held-to-maturity debt securities
Amortized cost, net		2,533	2,210
Gross unrealized gains		0	0
Gross unrealized losses		29	58
Fair value		2,504	2,152
Asset-backed securities
Held-to-maturity debt securities
Amortized cost, net		30,499	30,046
Gross unrealized gains		65	9
Gross unrealized losses		65	135
Fair value		$ 30,499	$ 29,920

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount, before tax and adjustment, of unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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