INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$ 35,515	$ 33,459
Securities held to maturity, fixed maturities, fair value	42,807	37,520
Assets, fair value	79,697	72,996
Variable Interest Entity, Not Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	4,908	4,731
Securities available for sale, fixed maturities, fair value	5,291	5,093
Securities available for sale, perpetual securities, amortized cost	266	249
Securities available for sale, perpetual securities, fair value	256	253
Securities held to maturity, fixed maturities, amortized cost	2,651	2,477
Securities held to maturity, fixed maturities, fair value	2,886	2,636
Assets, amortized cost	7,825	7,457
Assets, fair value	$ 8,433	$ 7,982

Assets, Amortized Cost Disclosure

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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 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
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-Publisher FASB
-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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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value of investments in debt securities classified as held-to-maturity.

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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.

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