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Investments (Details Textual) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 USD ($) security | Mar. 31, 2015 USD ($) | 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 | 57.00% |  |
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 79.00% |  |
Other than temporary impairment charges | $ 52 | $ 4 |
Average life of ABS | 5 years |  |
Average life of MBS | 4 years 6 months |  |
Residential Mortgage Backed Securities [Member] |  |  |
Investment [Line Items] |  |  |
Non-credit related portion of other-than-temporary impairment charges taken for securities still owned | $ 201 |  | $ 205
Fixed maturities, Gross Unrealized, Losses | (26) |  | (15)
Other than temporary impairment charges | 2 |  |
Securities with non-credit other-than-temporary impairment charges [Member] |  |  |
Investment [Line Items] |  |  |
Gross Unrealized, Gains | 126 |  | 134
Gross Unrealized, Losses | (9) |  | (6)
Fixed maturities [Member] |  |  |
Investment [Line Items] |  |  |
Fixed maturities, Gross Unrealized, Losses | $ (280) |  | (374)
Number of available for sale securities in an unrealized loss position | security | 868 |  |
Other than temporary impairment charges | $ 16 | $ 5 |
Corporate bonds [Member] |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges | $ 14 |  |
Common stocks [Member] |  |  |
Investment [Line Items] |  |  |
Number of available for sale securities in an unrealized loss position | security | 63 |  |
Other than temporary impairment charges | $ 38 |  |
Equity securities, Gross Unrealized, Losses | $ (81) |  | (79)
Preferred stocks [Member] |  |  |
Investment [Line Items] |  |  |
Number of available for sale securities in an unrealized loss position | security | 24 |  |
Other than temporary impairment charges | $ 3 |  |
Equity securities, Gross Unrealized, Losses | $ (9) |  | $ (6)
Number of available for sale securities in an unrealized loss position for twelve months or longer [Member] | Common stocks [Member] |  |  |
Investment [Line Items] |  |  |
Number of available for sale securities in an unrealized loss position | security | 1 |  |
Number of available for sale securities in an unrealized loss position for twelve months or longer [Member] | Preferred stocks [Member] |  |  |
Investment [Line Items] |  |  |
Number of available for sale securities in an unrealized loss position | security | 3 |  |

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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 + Details
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