FAIR VALUE DISCLOSURES (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 1,451	$ 1,109
Risk-adjusted discount factor	7.00%
Level 1
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 4	$ 9
Percentage of assets measured at fair value on recurring basis	56.90%	61.30%
Level 2
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 1,441	$ 1,069
Percentage of assets measured at fair value on recurring basis	42.90%	37.70%
Level 3
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 6	$ 31
Percentage of assets measured at fair value on recurring basis	0.20%	1.00%
Mortgage, asset-backed securities and CBMS measured at fair value	$ 0	$ 24
Public Fixed Maturities
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 1,149	$ 888
Percentage of available-for-sale, fixed maturity measured at fair value	31.90%	29.40%
Private Fixed Maturities
Fair Value Financial Instruments [Line Items]
Fixed maturity securities, fair value	$ 302	$ 221
Percentage of available-for-sale, fixed maturity measured at fair value	8.40%	7.30%
Minimum
Fair Value Financial Instruments [Line Items]
Investment term	1 year
Maximum
Fair Value Financial Instruments [Line Items]
Investment term	3 years

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- Definition

Investment Term

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- Definition

Percentage of assets at fair value on recurring basis by fair value inputs level.

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No definition available.

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- Definition

This element represent the percentage of available for sale fixed maturities measured at fair value on a recurring basis as a percentage of total assets measured at fair value on a recurring basis.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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- Definition

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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