Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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- Definition

Amount of other-than-temporary impairment (OTTI) on total investments, recognized in earnings. Includes investment in debt securities and other investments.

+ References

No definition available.

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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

No definition available.

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Investments (Details) - Impairment Charges - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment Information
Fixed maturities impairment charges	$ 1
Total investments impairment charges	1
Impairment charges		$ 14	$ 29
Fixed maturities [Member]
Investment Information
Impairment charges		4	15
All other corporate bonds [Member]
Investment Information
Fixed maturities impairment charges	$ 1
Impairment charges		4	15
Equity securities [Member]
Investment Information
Impairment charges		9	12
Public common stock [Member]
Investment Information
Impairment charges		9	9
Non-redeemable preferred stock [Member]
Investment Information
Impairment charges			3
Other investments [Member]
Investment Information
Impairment charges		$ 1	$ 2