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Investments (Details 3) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2012 | Dec. 31, 2011
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Summary of the cost or amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale, by contractual maturity |  |
Due in 2013, Amortized Cost | $ 7,239 |
In 2014 through 2017, Amortized cost | 24,641 |
In 2018 through 2022, Amortized cost | 18,708 |
After 2021, Amortized cost | 81,985 |
U.S. agency-based mortgage-backed securities, Amortized Cost | 11,941 |
Total, Amortized Cost | 144,514 | 98,077
Due in 2013, Fair value | 7,223 |
In 2014 through 2017, Fair value | 25,003 |
In 2018 through 2022, Fair value | 19,342 |
After 2021, Fair value | 86,484 |
U.S. agency-based mortgage-backed securities, Fair Value | 11,087 |
Total, Fair Value | $ 149,139 |

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