FAIR VALUE DISCLOSURES - FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	$ 1,451	$ 1,109
Trading securities	1	1
Options	89	56
Cash equivalents	44	109
Separate Accounts assets	2,013	1,746
Total Assets	3,598	3,021
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	92	60
Public corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	907	827
Private corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	291	208
U.S. Treasury, government and agency
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	232	35
States and political subdivisions
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	5	6
Commercial mortgage-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value		24
Asset-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	12
Redeemable preferred stock
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	4	9
Contingent payment arrangements
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	4	7
MSO and IUL indexed features’ liability
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	88	53
Level 1
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	4	9
Trading securities	1	1
Options	0	0
Cash equivalents	44	109
Separate Accounts assets	1,999	1,732
Total Assets	2,048	1,851
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	0	0
Level 1 \| Public corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 1 \| Private corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 1 \| U.S. Treasury, government and agency
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 1 \| States and political subdivisions
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 1 \| Commercial mortgage-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value		0
Level 1 \| Asset-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0
Level 1 \| Redeemable preferred stock
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	4	9
Level 1 \| Contingent payment arrangements
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	0	0
Level 1 \| MSO and IUL indexed features’ liability
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	0	0
Level 2
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	1,441	1,069
Trading securities	0	0
Options	89	56
Cash equivalents	0	0
Separate Accounts assets	14	14
Total Assets	1,544	1,139
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	88	53
Level 2 \| Public corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	907	827
Level 2 \| Private corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	285	201
Level 2 \| U.S. Treasury, government and agency
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	232	35
Level 2 \| States and political subdivisions
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	5	6
Level 2 \| Commercial mortgage-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value		0
Level 2 \| Asset-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	12
Level 2 \| Redeemable preferred stock
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 2 \| Contingent payment arrangements
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	0	0
Level 2 \| MSO and IUL indexed features’ liability
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	88	53
Level 3
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	6	31
Trading securities	0	0
Options	0	0
Cash equivalents	0	0
Separate Accounts assets	0	0
Total Assets	6	31
Liabilities, Fair Value Disclosure [Abstract]
Total liabilities	4	7
Level 3 \| Public corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 3 \| Private corporate
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	6	7
Level 3 \| U.S. Treasury, government and agency
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 3 \| States and political subdivisions
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 3 \| Commercial mortgage-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value		24
Level 3 \| Asset-backed
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0
Level 3 \| Redeemable preferred stock
Assets, Fair Value Disclosure [Abstract]
Fixed maturity securities, fair value	0	0
Level 3 \| Contingent payment arrangements
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	4	7
Level 3 \| MSO and IUL indexed features’ liability
Liabilities, Fair Value Disclosure [Abstract]
Guarantees	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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Fair value of financial and nonfinancial obligations.

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Fair value amount of the specified investment category of assets maintained in separate accounts as of the balance sheet date.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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