DERIVATIVE INSTRUMENTS - Gains (Losses) Recognized on Fair Value Hedging Relationships (Details) (Fixed Maturities, USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	$ (1,835)	$ (1,735)	$ (535)
Gains (losses) on derivatives excluded from effectiveness testing	(38)	(25)	(8)
Gains (losses) on derivatives included in effectiveness testing	(1,797)	(1,710)	(527)
Gains (losses) recognized for hedged items	1,819	1,700	528
Ineffectiveness recognized for fair value hedge	22	(10)	1
Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	(41)
Gains (losses) on derivatives excluded from effectiveness testing	(4)
Gains (losses) on derivatives included in effectiveness testing	(37)
Gains (losses) recognized for hedged items	38
Ineffectiveness recognized for fair value hedge	1
Interest rate swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	(318)	17
Gains (losses) on derivatives excluded from effectiveness testing	(36)	17
Gains (losses) on derivatives included in effectiveness testing	(282)	0
Gains (losses) recognized for hedged items	316	0
Ineffectiveness recognized for fair value hedge	$ 34	$ 0

Gain (loss) from components included in assessment of fair value hedge effectiveness net

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

+ References

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- Definition

Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

+ References

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