SECURITIES - Schedule of Cumulative Credit Losses Recognized in Earnings (Details) (Available-for-sale Securities, USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Available-for-sale Securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Cumulative balance at beginning of period	$ 62	$ 56
Credit impairments recognized in earnings on debt securities that have been previously impaired	1	4
Reductions due to increases in cash flow expectations on impaired securities	(1)	(1)
Cumulative balance at end of period	$ 62	$ 59

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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Balance Type:	debit
Period Type:	duration

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held due to increases in cash flows expected to be collected and recognized over the remaining life of the security.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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Balance Type:	credit
Period Type:	duration

- Details

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