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Investments (Details Textual) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2015 USD ($) | Jun. 30, 2014 USD ($) | Jun. 30, 2015 USD ($) investment security | Jun. 30, 2014 USD ($) | Dec. 31, 2014 USD ($) investment
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 |  |  | 83.00% |  |
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 | $ 30 | $ 1 | $ 34 | $ 2 |
Average life of ABS |  |  | 5 years |  |
Average life of MBS |  |  | 4 years 6 months |  |
The number of investments in individual issuers that exceeded 10% of Shareholders’ Equity | investment |  |  | 0 |  | 0
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 | 216 |  | $ 216 |  | $ 220
Fixed maturities, Gross Unrealized, Losses | (13) |  | (13) |  | (15)
Securities with non-credit other-than-temporary impairment charges [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Gross Unrealized, Gains | 148 |  | 148 |  | 151
Gross Unrealized, Losses | (7) |  | (7) |  | (8)
Fixed maturities [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Fixed maturities, Gross Unrealized, Losses | (169) |  | $ (169) |  | (79)
Number of available for sale securities in an unrealized loss position | security |  |  | 1,040 |  |
Other than temporary impairment charges | 10 | $ 0 | $ 15 | $ 1 |
Corporate bonds [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Other than temporary impairment charges |  |  | 10 |  |
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 |  |  | 47 |  |
Other than temporary impairment charges |  |  | $ 25 |  |
Equity securities, Gross Unrealized, Losses | (30) |  | $ (30) |  | (25)
Preferred stocks [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Number of available for sale securities in an unrealized loss position | security |  |  | 22 |  |
Equity securities, Gross Unrealized, Losses | $ (5) |  | $ (5) |  | $ (5)
Maximum [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |  |
Investment [Line Items] |  |  |  |  |
Other than temporary impairment charges |  |  | $ 1 |  |
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 |  |  | 3 |  |

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