FAIR VALUE MEASUREMENT - Valuation Techniques and Inputs for Level 3 Nonrecurring Fair Value Measurements (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Nonrecurring fair value changes included in earnings
Nonrecurring fair value measurements included in earnings	$ (515,000,000)	$ (767,000,000)
Loans held-for-sale
Nonrecurring fair value changes included in earnings
Nonrecurring fair value measurements included in earnings	34,000,000	0
Other real estate owned
Nonrecurring fair value changes included in earnings
Nonrecurring fair value measurements included in earnings	(16,000,000)	(6,000,000)
Loans
Nonrecurring fair value changes included in earnings
Nonrecurring fair value measurements included in earnings	(533,000,000)	(761,000,000)
Nonrecurring \| Level 3
Valuation techniques and inputs
Total assets	3,635,000,000	2,207,000,000
Nonrecurring \| Level 3 \| Loans held-for-sale \| Price-based
Valuation techniques and inputs
Total assets	2,740,000,000	912,000,000
Nonrecurring \| Level 3 \| Loans held-for-sale \| Price-based \| Minimum
Valuation techniques and inputs
Price	92.00	60.00
Credit spread	0.05%
Nonrecurring \| Level 3 \| Loans held-for-sale \| Price-based \| Maximum
Valuation techniques and inputs
Price	100.00	100.00
Credit spread	3.58%
Nonrecurring \| Level 3 \| Loans held-for-sale \| Price-based \| Weighted Average
Valuation techniques and inputs
Price	99.54	98.77
Credit spread	1.75%
Nonrecurring \| Level 3 \| Loans held-for-sale \| Cash flow
Valuation techniques and inputs
Total assets		393,000,000
Nonrecurring \| Level 3 \| Loans held-for-sale \| Cash flow \| Minimum
Valuation techniques and inputs
Credit spread		0.45%
Nonrecurring \| Level 3 \| Loans held-for-sale \| Cash flow \| Maximum
Valuation techniques and inputs
Credit spread		0.80%
Nonrecurring \| Level 3 \| Loans held-for-sale \| Cash flow \| Weighted Average
Valuation techniques and inputs
Credit spread		0.64%
Nonrecurring \| Level 3 \| Other real estate owned \| Price-based
Valuation techniques and inputs
Total assets	76,000,000	98,000,000
Nonrecurring \| Level 3 \| Other real estate owned \| Price-based \| Minimum
Valuation techniques and inputs
Appraised value	11,000
Discount to price (as a percent)	13.00%	34.00%
Nonrecurring \| Level 3 \| Other real estate owned \| Price-based \| Maximum
Valuation techniques and inputs
Appraised value	11,124,137
Discount to price (as a percent)	64.00%	59.00%
Nonrecurring \| Level 3 \| Other real estate owned \| Price-based \| Weighted Average
Valuation techniques and inputs
Appraised value	4,730,129
Discount to price (as a percent)	28.80%	39.00%
Nonrecurring \| Level 3 \| Other real estate owned \| Cash flow
Valuation techniques and inputs
Total assets		17,000,000
Nonrecurring \| Level 3 \| Other real estate owned \| Cash flow \| Minimum
Valuation techniques and inputs
Price		60.46
Appraised value		636,249
Nonrecurring \| Level 3 \| Other real estate owned \| Cash flow \| Maximum
Valuation techniques and inputs
Price		100.00
Appraised value		15,897,503
Nonrecurring \| Level 3 \| Other real estate owned \| Cash flow \| Weighted Average
Valuation techniques and inputs
Price		96.67
Appraised value		11,392,478
Nonrecurring \| Level 3 \| Loans \| Price-based
Valuation techniques and inputs
Total assets	437,000,000	581,000,000
Nonrecurring \| Level 3 \| Loans \| Price-based \| Minimum
Valuation techniques and inputs
Discount to price (as a percent)	13.00%	34.00%
Nonrecurring \| Level 3 \| Loans \| Price-based \| Maximum
Valuation techniques and inputs
Discount to price (as a percent)	34.00%	39.00%
Nonrecurring \| Level 3 \| Loans \| Price-based \| Weighted Average
Valuation techniques and inputs
Discount to price (as a percent)	28.92%	35.00%
Nonrecurring \| Level 3 \| Loans \| Model-based
Valuation techniques and inputs
Total assets		109,000,000
Nonrecurring \| Level 3 \| Loans \| Model-based \| Minimum
Valuation techniques and inputs
Price		52.40
Appraised value		6,500,000
Nonrecurring \| Level 3 \| Loans \| Model-based \| Maximum
Valuation techniques and inputs
Price		68.00
Appraised value		86,000,000
Nonrecurring \| Level 3 \| Loans \| Model-based \| Weighted Average
Valuation techniques and inputs
Price		65.32
Appraised value		$ 43,532,719

Fair Value Inputs Appraised Value

No definition available.

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- Definition

Represents the rate of financial derivative contract that transfers credit risk from one party to another, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Represents the discount to price, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

The price input is a significant unobservable input for certain fixed income instruments. For these instruments, the price input is expressed as a percentage of the notional amount, with a price of $100 meaning that the instrument is valued at par. For most of these instruments, the price varies between zero to $100, or slightly above $100. Relatively illiquid assets that have experienced significant losses since issuance, such as certain asset-backed securities, are at the lower end of the range, whereas most investment grade corporate bonds will fall in the middle to the higher end of the range. For certain structured debt instruments with embedded derivatives, the price input may be above $100 to reflect the embedded features of the instrument (for example, a step-up coupon or a conversion option). The price input is also a significant unobservable input for certain equity securities; however, the range of price inputs varies depending on the nature of the position, the number of shares outstanding and other factors. Because of these factors, the weighted average price input for equity securities does not provide insight regarding the central tendencies of the ranges for equity securities, as equity prices are generally independent of one another and are not subject to a common measurement scale (for example, the zero to $100 range applicable to debt instruments). Prices for loan-held-for-sale and other real estate owned are based on appraised values.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in the income statement for an asset measured on a nonrecurring basis using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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