ALLOWANCE FOR CREDIT LOSSES - Allowance for Credit Losses Roll Forward by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	$ 16,974	$ 16,455
Charge-offs	(1,634)	(1,240)
Recoveries	332	368
Replenishment of NCLs	1,302	872
Net reserve builds (releases)	397	(781)
Net specific reserve builds (releases)	38	169
Other	112	(450)
ACLL at end of period	17,169	15,393
ACLL
Collectively evaluated	16,802		$ 16,053
Individually evaluated	368		919
Total ACLL	17,169	15,393	16,974
Loans, net of unearned income
Collectively evaluated	645,496		647,704
Individually evaluated	1,252		4,043
Loans held at fair value	5,134		5,360
Loans, net of unearned income	651,995		657,221
Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	(352)	0
ACLL
Total ACLL			(352)
Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	16,622	16,455
ACLL
Total ACLL			16,622
Purchased credit deteriorated
ACLL
Purchased credit deteriorated	(1)		2
Loans, net of unearned income
Purchased credit deteriorated	113		114
Corporate
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	2,855	2,415
Charge-offs	(39)	(48)
Recoveries	17	17
Replenishment of NCLs	22	31
Net reserve builds (releases)	(90)	376
Net specific reserve builds (releases)	5	225
Other	10	9
ACLL at end of period	2,780	3,025
ACLL
Collectively evaluated	2,451		2,532
Individually evaluated	329		323
Total ACLL	2,780	3,025	2,855
Loans, net of unearned income
Collectively evaluated	282,190		282,909
Individually evaluated	1,213		1,122
Loans held at fair value	4,896		5,123
Loans, net of unearned income	288,299		289,154
Corporate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	0	0
ACLL
Total ACLL			0
Corporate \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	2,855	2,415
ACLL
Total ACLL			2,855
Corporate \| Purchased credit deteriorated
ACLL
Purchased credit deteriorated	0		0
Loans, net of unearned income
Purchased credit deteriorated	0		0
Consumer
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	14,119	14,040
Charge-offs	(1,595)	(1,192)
Recoveries	315	351
Replenishment of NCLs	1,280	841
Net reserve builds (releases)	487	(1,157)
Net specific reserve builds (releases)	33	(56)
Other	102	(459)
ACLL at end of period	14,389	12,368
ACLL
Collectively evaluated	14,351		13,521
Individually evaluated	39		596
Total ACLL	14,389	12,368	14,119
Loans, net of unearned income
Collectively evaluated	363,306		364,795
Individually evaluated	39		2,921
Loans held at fair value	238		237
Loans, net of unearned income	363,696		368,067
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	(352)	0
ACLL
Total ACLL			(352)
Consumer \| Cumulative Effect, Period of Adoption, Adjusted Balance
Allowance for credit losses
Allowance for credit losses on loans (ACLL) at beginning of period	13,767	$ 14,040
ACLL
Total ACLL			13,767
Consumer \| Purchased credit deteriorated
ACLL
Purchased credit deteriorated	(1)		2
Loans, net of unearned income
Purchased credit deteriorated	$ 113		$ 114

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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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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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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The balance of financing receivables that were individually evaluated for impairment.

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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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