ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 18,574	$ 18,145
Charge-offs	(2,926)	(2,690)
Recoveries	467	387
Replenishment of NCLs	2,459	2,303
Net reserve builds (releases)	227	246
Net specific reserve builds (releases)	(125)	(127)
Other	50	32
ACLL at end of period	18,726	18,296
ACLL
Collectively evaluated	18,510		$ 18,221
Individually evaluated	215		340
Total ACLL	18,726	18,296	18,574
Loans, net of unearned income
Collectively evaluated	692,264		684,812
Individually evaluated	1,510		1,511
Held at fair value	8,165		8,040
Total loans, net of unearned income	702,056		694,488
Purchased credit deteriorated
ACLL
Purchased credit deteriorated	1		13
Loans, net of unearned income
Purchased credit deteriorated	117		125
Corporate loans
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	2,556	2,714
Charge-offs	(199)	(178)
Recoveries	17	14
Replenishment of NCLs	182	164
Net reserve builds (releases)	279	188
Net specific reserve builds (releases)	(125)	(131)
Other	15	1
ACLL at end of period	2,725	2,772
ACLL
Collectively evaluated	2,548		2,254
Individually evaluated	177		302
Total ACLL	2,725	2,772	2,556
Loans, net of unearned income
Collectively evaluated	306,481		292,250
Individually evaluated	1,376		1,377
Held at fair value	7,887		7,759
Total loans, net of unearned income	315,744		301,386
Corporate loans \| Purchased credit deteriorated
ACLL
Purchased credit deteriorated	0		0
Loans, net of unearned income
Purchased credit deteriorated	0		0
Consumer loans
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	16,018	15,431
Charge-offs	(2,727)	(2,512)
Recoveries	450	373
Replenishment of NCLs	2,277	2,139
Net reserve builds (releases)	(52)	58
Net specific reserve builds (releases)	0	4
Other	35	31
ACLL at end of period	16,001	15,524
ACLL
Collectively evaluated	15,962		15,967
Individually evaluated	38		38
Total ACLL	16,001	$ 15,524	16,018
Loans, net of unearned income
Collectively evaluated	385,783		392,562
Individually evaluated	134		134
Held at fair value	278		281
Total loans, net of unearned income	386,312		393,102
Consumer loans \| Purchased credit deteriorated
ACLL
Purchased credit deteriorated	1		13
Loans, net of unearned income
Purchased credit deteriorated	$ 117		$ 125

Financing Receivable, Excluding Accrued Interest, Allowance For Credit Loss, Adjustments, Other

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Financing Receivable, Excluding Accrued Interest, Allowance for Credit Losses, Purchased Credit-Deteriorated

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No definition available.

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Provision charged or released during the period against earnings for credit losses on loans and leases receivable that are expected and were collectively evaluated for impairment.

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Provision charged or released during the period against earnings for credit losses on loans and leases receivable that are expected and were individually evaluated for impairment.

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Financing Receivable, Purchased Credit-Deteriorated

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of allowance for credit loss on financing receivable evaluated on collective basis. Excludes financing receivable evaluated on individual basis.

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Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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Amount of financing receivable collectively evaluated for credit loss. Excludes financing receivable individually evaluated for credit loss.

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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