Asset-backed securities average useful life.

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- Definition

Mortgage backed securities average useful life.

+ References

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- Definition

Non-credit related portion of other-than-temporary impairment charges taken for securities still owned.

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No definition available.

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- Definition

Number of available-for-sale securities in an unrealized loss position.

+ References

No definition available.

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- Definition

Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade.

+ References

No definition available.

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- Definition

Percentage based on unrealized loss of available for sale fixed maturities that are in an unrealized loss position and rated investment grade.

+ References

No definition available.

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- Definition

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.

+ References

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 before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

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Investments - Narrative (Details) $ in Millions	12 Months Ended
Investments - Narrative (Details) $ in Millions	Dec. 31, 2017 USD ($) security	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Investment [Line Items]
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	78.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	90.00%
Other than temporary impairment charges	$ 73	$ 116	$ 125
Average life of ABS	5 years
Average life of MBS	4 years 6 months
Residential MBS
Investment [Line Items]
Non-credit related portion of other-than-temporary impairment charges taken for securities still owned	$ 158	189
Fixed maturities, Gross Unrealized, Losses	(6)	(13)
Other than temporary impairment charges	1
Fixed Maturities excluding Residential MBS
Investment [Line Items]
Other than temporary impairment charges	19
Securities with non-credit other-than-temporary impairment charges
Investment [Line Items]
Gross Unrealized, Gains	137	130
Gross Unrealized, Losses	(4)	(3)
Fixed maturities
Investment [Line Items]
Fixed maturities, Gross Unrealized, Losses	$ (82)	(245)
Number of available for sale securities in an unrealized loss position \| security	841
Other than temporary impairment charges	$ 20	38	$ 43
Other investments
Investment [Line Items]
Other than temporary impairment charges	$ 4
Common stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position \| security	16
Other than temporary impairment charges	$ 55
Equity securities, Gross Unrealized, Losses	$ (22)	(23)
Preferred stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position \| security	7
Other than temporary impairment charges	$ 9
Equity securities, Gross Unrealized, Losses	$ (1)	$ (7)
Number of available for sale securities in an unrealized loss position for twelve months or longer \| Common stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position \| security	0
Number of available for sale securities in an unrealized loss position for twelve months or longer \| Preferred stocks
Investment [Line Items]
Number of available for sale securities in an unrealized loss position \| security	3