SCHEDULE I - SUMMARY OF INVESTMENTS - OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Millions	Dec. 31, 2017 USD ($)
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	$ 1,690
Fair Value	1,755
Carrying Value	1,716
U.S. Treasury, government and agency
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	232
Fair Value	232
Carrying Value	232
States and political subdivisions
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	5
Fair Value	5
Carrying Value	5
Public utilities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	209
Fair Value	212
Carrying Value	212
All other corporate bonds
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	963
Fair Value	986
Carrying Value	986
Asset-backed
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	12
Fair Value	12
Carrying Value	12
Redeemable preferred stock
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	4
Fair Value	4
Carrying Value	4
Fixed Maturities
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	1,425
Fair Value	1,451
Carrying Value	1,451
Mortgage loans on real estate
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	17
Fair Value	17
Carrying Value	17
Policy Loans
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	185
Fair Value	224
Carrying Value	185
Other Invested Assets
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	63
Fair Value	63
Carrying Value	$ 63

This element represents the carrying (reported) amount of the entity's investments as of the balance sheet date. This amount may represent the individual investment's or group of similar investments' original cost, fair value, or such other amount at which the investment is shown in the entity's balance sheet.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15)
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611379-123010

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