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Investments (Details Textual) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 USD ($) | Sep. 30, 2014 USD ($) | Sep. 30, 2015 USD ($) security | Sep. 30, 2014 USD ($) | Dec. 31, 2014 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 |  |  | 76.00% |  |
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade |  |  | 85.00% |  |
Other than temporary impairment charges | $ 35 | $ 11 | $ 69 | $ 13 |
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 | 213 |  | $ 213 |  | $ 220
Fixed maturities, Gross Unrealized, Losses | (15) |  | (15) |  | (15)
Other than temporary impairment charges |  |  | 3 |  |
Securities with non-credit other-than-temporary impairment charges [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Gross Unrealized, Gains | 143 |  | 143 |  | 151
Gross Unrealized, Losses | (8) |  | (8) |  | (8)
Fixed maturities [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Fixed maturities, Gross Unrealized, Losses | (211) |  | $ (211) |  | (79)
Number of available for sale securities in an unrealized loss position | security |  |  | 950 |  |
Other than temporary impairment charges | 17 | $ 9 | $ 32 | $ 10 |
Corporate bonds [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Other than temporary impairment charges |  |  | 25 |  |
Municipal bonds [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Other than temporary impairment charges |  |  | $ 4 |  |
Common stocks [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Number of available for sale securities in an unrealized loss position | security |  |  | 76 |  |
Other than temporary impairment charges |  |  | $ 48 |  |
Equity securities, Gross Unrealized, Losses | (94) |  | $ (94) |  | (25)
Preferred stocks [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Number of available for sale securities in an unrealized loss position | security |  |  | 25 |  |
Equity securities, Gross Unrealized, Losses | $ (7) |  | $ (7) |  | $ (5)
Percentage (based on amount of unrealized loss) of available for sale equity securities that are in an unrealized loss position for twelve months or more and rated investment grade |  |  | 93.00% |  |
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 |  |  | 0 |  |
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 |  |  | 4 |  |

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