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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 |

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- Definition Asset-backed securities average useful life. + References No definition available. + Details
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Balance Type: | na
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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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- 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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