INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$ 34,242us-gaap_HeldToMaturitySecurities	$ 44,415us-gaap_HeldToMaturitySecurities
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Assets, fair value	73,901us-gaap_AssetsFairValueDisclosure	64,532us-gaap_AssetsFairValueDisclosure
Variable Interest Entity, Not Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	6,104	6,724
Securities available for sale, fixed maturities, fair value	6,937	6,916
Securities available for sale, perpetual securities, amortized cost	324	370
Securities available for sale, perpetual securities, fair value	330	378
Securities held to maturity, fixed maturities, amortized cost	2,564	2,949
Securities held to maturity, fixed maturities, fair value	2,829	3,039
Assets, amortized cost	8,992	10,043
Assets, fair value	$ 10,096	$ 10,333

Assets, Amortized Cost Disclosure

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- Definition

For an unclassified balance sheet, total of perpetual securities categorized as neither held-to-maturity nor trading. Perpetual securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below cost basis.

+ References

No definition available.

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This item represents the aggregate amortized cost of investments in perpetual securities as of the balance sheet date and which are categorized as available-for-sale.

+ References

No definition available.

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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)

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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-Name Accounting Standards Codification

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

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