Investments (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2014 security	Mar. 31, 2013	Dec. 31, 2013
Investment [Line Items]
Number of available for sale fixed maturities in an unrealized loss position	825
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	83.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	88.00%
Other than temporary impairment charges (are less than in 2014)	$ 1	$ 0
Average life of ABS	5 years 0 months
Average life of MBS	4 years 6 months
Percentage increase in shareholders' equity	10.00%		10.00%
Residential Mortgage Backed Securities [Member]
Investment [Line Items]
Non-credit related portion of other-than-temporary impairment charges taken for securities still owned	224		229
Gross Unrealized, Gains	412		391
Gross Unrealized, Losses	(24)		(28)
Other than temporary impairment charges (are less than in 2014)	1
Securities with non-credit other-than-temporary impairment charges [Member]
Investment [Line Items]
Gross Unrealized, Gains	153		150
Gross Unrealized, Losses	(11)		(13)
Fixed maturities [Member]
Investment [Line Items]
Gross Unrealized, Gains	1,569		1,395
Gross Unrealized, Losses	(163)		(305)
Other than temporary impairment charges (are less than in 2014)	$ 1	$ 0

Asset-backed securities average useful life.

No definition available.

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- Definition

Amount of accumulated unrealized gain before deducting unrealized loss on investments in available-for-sale securities impacting investments.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss before deducting unrealized gain on investments in available-for-sale securities impacting investments.

+ References

No definition available.

+ Details

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- Definition

Investments in individual issuers as percentage of shareholders equity.

+ References

No definition available.

+ Details

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- Definition

Mortgage backed securities average useful life.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number of Available For Sale Securities In An Unrealized Loss Position.

+ References

No definition available.

+ Details

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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.

+ Details

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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.

+ Details

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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 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

+ Details

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