ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses Roll Forward by Segment (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Allowance for credit losses
Allowance for loan losses at beginning of period	$ 15,994	$ 19,648
Charge-offs	(2,458)	(2,983)
Recoveries	501	544
Replenishment of net charge-offs	1,957	2,439
Net reserve build (releases)	(91)	(560)
Net specific reserve releases	(111)	(86)
Other	(1,194)	(79)
Allowance for loan losses at the end of year	14,598	18,923
Allowance for loan losses:
Determined in accordance with ASC 450-20	10,994		11,783
Determined in accordance with ASC 310-10-35	3,550		4,152
Allowance for loan losses	14,598	18,923
Loans, net of unearned income:
Loans collectively evaluated for impairment in accordance with ASC 450-20	596,976		617,470
Loans individually evaluated for impairment in accordance with ASC 310-10-35	17,105		20,843
Loans held at fair value	6,575		5,901
Loans, net of unearned income	621,054		644,635
Receivables Acquired with Deteriorated Credit Quality
Allowance for loan losses:
Determined in accordance with ASC 310-30	54		59
Loans, net of unearned income:
Loans	398		421
Corporate
Allowance for credit losses
Allowance for loan losses at beginning of period	2,389	2,584
Charge-offs	(23)	(174)
Recoveries	32	29
Replenishment of net charge-offs	(9)	145
Net reserve build (releases)	100	(101)
Net specific reserve releases	3	(10)
Other	(16)	(1)
Allowance for loan losses at the end of year	2,476	2,472
Allowance for loan losses:
Determined in accordance with ASC 450-20	2,201		2,110
Determined in accordance with ASC 310-10-35	236		235
Allowance for loan losses	2,476	2,472
Loans, net of unearned income:
Loans collectively evaluated for impairment in accordance with ASC 450-20	271,335		267,271
Loans individually evaluated for impairment in accordance with ASC 310-10-35	1,431		1,485
Loans held at fair value	6,537		5,858
Loans, net of unearned income	279,348		274,665
Corporate \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loan losses:
Determined in accordance with ASC 310-30	39		44
Loans, net of unearned income:
Loans	45		51
Consumer
Allowance for credit losses
Allowance for loan losses at beginning of period	13,605	17,064
Charge-offs	(2,435)	(2,809)
Recoveries	469	515
Replenishment of net charge-offs	1,966	2,294
Net reserve build (releases)	(191)	(459)
Net specific reserve releases	(114)	(76)
Other	(1,178)	(78)
Allowance for loan losses at the end of year	12,122	16,451
Allowance for loan losses:
Determined in accordance with ASC 450-20	8,793		9,673
Determined in accordance with ASC 310-10-35	3,314		3,917
Allowance for loan losses	12,122	16,451
Loans, net of unearned income:
Loans collectively evaluated for impairment in accordance with ASC 450-20	325,641		350,199
Loans individually evaluated for impairment in accordance with ASC 310-10-35	15,674		19,358
Loans held at fair value	38		43
Loans, net of unearned income	341,706		369,970
Consumer \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loan losses:
Determined in accordance with ASC 310-30	15		15
Loans, net of unearned income:
Loans	$ 353		$ 370

Reflects the amount of replenishment of net charge-offs for credit losses.

No definition available.

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- Definition

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.

+ References

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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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Amount of other addition (reduction) in allowance reserve for credit loss.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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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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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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