ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 19,247	$ 18,574
Charge-offs	(2,820)	(2,926)
Recoveries	612	467
Replenishment of NCLs	2,208	2,459
Net reserve builds (releases)	301	227
Net specific reserve builds (releases)	96	(125)
Other	(8)	50
ACLL at end of period	19,636	18,726
ACLL
Collectively evaluated	19,170		$ 18,874
Individually evaluated	468		374
Total ACLL	19,636	18,726	19,247
Loans, net of unearned income
Collectively evaluated	750,969		743,117
Individually evaluated	2,024		2,150
Held at fair value	8,523		6,855
Total loans, net of unearned income	761,616		752,230
Purchased credit deteriorated
ACLL
Purchased credit deteriorated	(2)		(1)
Loans, net of unearned income
Purchased credit deteriorated	100		108
Corporate loans
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	3,053	2,556
Charge-offs	(42)	(199)
Recoveries	34	17
Replenishment of NCLs	8	182
Net reserve builds (releases)	203	279
Net specific reserve builds (releases)	96	(125)
Other	(13)	15
ACLL at end of period	3,339	2,725
ACLL
Collectively evaluated	2,922		2,730
Individually evaluated	417		323
Total ACLL	3,339	2,725	3,053
Loans, net of unearned income
Collectively evaluated	348,770		334,892
Individually evaluated	1,957		2,001
Held at fair value	8,498		6,804
Total loans, net of unearned income	359,225		343,697
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	16,194	16,018
Charge-offs	(2,778)	(2,727)
Recoveries	578	450
Replenishment of NCLs	2,200	2,277
Net reserve builds (releases)	98	(52)
Net specific reserve builds (releases)	0	0
Other	5	35
ACLL at end of period	16,297	16,001
ACLL
Collectively evaluated	16,248		16,144
Individually evaluated	51		51
Total ACLL	16,297	$ 16,001	16,194
Loans, net of unearned income
Collectively evaluated	402,199		408,225
Individually evaluated	67		149
Held at fair value	25		51
Total loans, net of unearned income	402,391		408,533
Consumer loans \| Purchased credit deteriorated
ACLL
Purchased credit deteriorated	(2)		(1)
Loans, net of unearned income
Purchased credit deteriorated	$ 100		$ 108

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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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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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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