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Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
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Consolidated Balance Sheets [Abstract] |  |
Fixed maturity securities, fair value | $ 685,242 | $ 683,463
Fixed maturity securities, cost | 98,077 | 21,865
Equity securities, cost | $ 11,776 | $ 1,687
Common stock, par value | $ 0.01 | $ 0.01
Common stock, shares authorized | 50,000,000 | 50,000,000
Common stock, shares issued | 19,408,512 | 19,060,649
Common stock, shares outstanding | 18,150,262 | 18,352,041
Treasury stock, at cost | 1,258,250 | 708,608

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