DERIVATIVE INSTRUMENTS - Gains (Losses) Recognized on Fair Value Hedging Relationships (Details) - Fixed maturities - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Foreign currency forwards
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	$ (133)	$ (1,835)	$ (1,735)
Gains (losses) on derivatives excluded from effectiveness testing	(136)	(38)	(25)
Gains (losses) on derivatives included in effectiveness testing	3	(1,797)	(1,710)
Gains (losses) recognized for hedged items	(5)	1,819	1,700
Ineffectiveness recognized for fair value hedge	(2)	22	(10)
Foreign currency options
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	(4)	(41)
Gains (losses) on derivatives excluded from effectiveness testing	3	(4)
Gains (losses) on derivatives included in effectiveness testing	(7)	(37)
Gains (losses) recognized for hedged items	7	38
Ineffectiveness recognized for fair value hedge	0	1
Interest rate swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) recognized for derivatives	(95)	(318)	17
Gains (losses) on derivatives excluded from effectiveness testing	19	(36)	17
Gains (losses) on derivatives included in effectiveness testing	(114)	(282)	0
Gains (losses) recognized for hedged items	99	316	0
Ineffectiveness recognized for fair value hedge	$ (15)	$ 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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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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