ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward by Segment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2023
Allowance for credit losses
Adjusted ACLL at beginning of year	$ 18,145	$ 16,974	$ 16,455
Charge-offs	(10,694)	(7,881)	(5,156)
Gross recoveries on loans	1,694	1,444	1,367
Replenishment of NCLs	9,000	6,437	3,789
Net reserve builds (releases) for loans	791	1,272	937
Net specific reserve builds (releases)	(65)	77	19
Other	(320)	174	(437)
ACLL at end of year	18,574	18,145	16,974
Allowance for credit losses on loans
Collectively evaluated(2)	18,221	17,743
Individually evaluated	340	402
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	18,574	18,145	16,974
Loans, net of unearned income
Collectively evaluated	684,812	679,713
Individually evaluated	1,511	1,940
Loans held at fair value	8,040	7,594
Total	694,488	689,362
Purchased credit deteriorated
Allowance for credit losses on loans
Purchased credit deteriorated	13	0
Loans, net of unearned income
Purchased credit deteriorated	125	115
Corporate
Allowance for credit losses
Adjusted ACLL at beginning of year	2,714	2,855	2,415
Charge-offs	(493)	(328)	(278)
Gross recoveries on loans	96	78	100
Replenishment of NCLs	397	250	178
Net reserve builds (releases) for loans	(67)	(168)	374
Net specific reserve builds (releases)	(63)	39	65
Other	(28)	(12)	1
ACLL at end of year	2,556	2,714	2,855
Allowance for credit losses on loans
Collectively evaluated(2)	2,254	2,352
Individually evaluated	302	362
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	2,556	2,714	2,855
Loans, net of unearned income
Collectively evaluated	292,250	291,002
Individually evaluated	1,377	1,882
Loans held at fair value	7,759	7,281
Total	301,386	300,165
Corporate \| Purchased credit deteriorated
Allowance for credit losses on loans
Purchased credit deteriorated	0	0
Loans, net of unearned income
Purchased credit deteriorated	0	0
Consumer
Allowance for credit losses
Adjusted ACLL at beginning of year	15,431	14,119	14,040
Charge-offs	(10,201)	(7,553)	(4,878)
Gross recoveries on loans	1,598	1,366	1,267
Replenishment of NCLs	8,603	6,187	3,611
Net reserve builds (releases) for loans	858	1,440	563
Net specific reserve builds (releases)	(2)	38	(46)
Other	(292)	186	(438)
ACLL at end of year	16,018	15,431	14,119
Allowance for credit losses on loans
Collectively evaluated(2)	15,967	15,391
Individually evaluated	38	40
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	16,018	15,431	14,119
Loans, net of unearned income
Collectively evaluated	392,562	388,711
Individually evaluated	134	58
Loans held at fair value	281	313
Total	393,102	389,197
Consumer \| Purchased credit deteriorated
Allowance for credit losses on loans
Purchased credit deteriorated	13	0
Loans, net of unearned income
Purchased credit deteriorated	$ 125	115
Cumulative effect of adoption
Allowance for credit losses
Adjusted ACLL at beginning of year		(352)
ACLL at end of year			(352)
Allowance for credit losses on loans
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			(352)	$ (352)
Adjusted balance
Allowance for credit losses
Adjusted ACLL at beginning of year		16,622
ACLL at end of year			16,622
Allowance for credit losses on loans
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			16,622
Adjusted balance \| Corporate
Allowance for credit losses
Adjusted ACLL at beginning of year		2,855
ACLL at end of year			2,855
Allowance for credit losses on loans
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			2,855
Adjusted balance \| Consumer
Allowance for credit losses
Adjusted ACLL at beginning of year		$ 13,767
ACLL at end of year			13,767
Allowance for credit losses on loans
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest			$ 13,767

Financing Receivable, Allowance For Credit Loss, Adjustments, Other

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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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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, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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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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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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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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