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Concentration of Operations (Tables) | 12 Months Ended
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Dec. 31, 2012
Concentration of Operations [Abstract] |
Net premiums earned for the different lines of business |
|  | 2012 |  |  | 2011 |  |  | 2010 |
| Dollars |  |  | Percent |  |  | Dollars |  |  | Percent |  |  | Dollars |  |  | Percent |
|  | (Dollars in thousands) |
Workers’ compensation |  | $ | 290,538 |  |  |  | 99.9 | % |  | $ | 249,966 |  |  |  | 99.6 | % |  | $ | 217,810 |  |  |  | 99.5 | %
General liability |  |  | 151 |  |  |  | 0.1 | % |  |  | 1,049 |  |  |  | 0.4 | % |  |  | 1,071 |  |  |  | 0.5 | %
Total net premiums earned |  | $ | 290,689 |  |  |  | 100.0 | % |  | $ | 251,015 |  |  |  | 100.0 | % |  | $ | 218,881 |  |  |  | 100.0 | %
Net premiums earned for the top ten states |
|  | 2012 |  |  | 2011 |  |  | 2010 |
| Dollars |  |  | Percent |  |  | Dollars |  |  | Percent |  |  | Dollars |  |  | Percent |
|  | (Dollars in thousands) |
Louisiana |  | $ | 31,134 |  |  |  | 10.7 | % |  | $ | 28,157 |  |  |  | 11.2 | % |  | $ | 23,406 |  |  |  | 10.7 | %
Georgia |  |  | 25,033 |  |  |  | 8.6 |  |  |  | 21,496 |  |  |  | 8.6 |  |  |  | 19,308 |  |  |  | 8.8 |
Pennsylvania |  |  | 24,480 |  |  |  | 8.4 |  |  |  | 19,265 |  |  |  | 7.7 |  |  |  | 16,784 |  |  |  | 7.7 |
North Carolina |  |  | 20,036 |  |  |  | 6.9 |  |  |  | 17,071 |  |  |  | 6.8 |  |  |  | 17,038 |  |  |  | 7.8 |
Illinois |  |  | 18,119 |  |  |  | 6.2 |  |  |  | 14,673 |  |  |  | 5.8 |  |  |  | 14,294 |  |  |  | 6.5 |
Oklahoma |  |  | 16,157 |  |  |  | 5.6 |  |  |  | 16,037 |  |  |  | 6.4 |  |  |  | 14,544 |  |  |  | 6.6 |
Virginia |  |  | 16,144 |  |  |  | 5.6 |  |  |  | 15,660 |  |  |  | 6.2 |  |  |  | 13,680 |  |  |  | 6.3 |
Texas |  |  | 11,687 |  |  |  | 4.0 |  |  |  | 11,073 |  |  |  | 4.4 |  |  |  | 8,858 |  |  |  | 4.0 |
Kansas |  |  | 10,925 |  |  |  | 3.8 |  |  |  | 9,486 |  |  |  | 3.8 |  |  |  | 7,126 |  |  |  | 3.3 |
Minnesota |  |  | 10,094 |  |  |  | 3.5 |  |  |  | 9,388 |  |  |  | 3.7 |  |  |  | 7,887 |  |  |  | 3.6 |
All others |  |  | 106,880 |  |  |  | 36.7 |  |  |  | 88,709 |  |  |  | 35.4 |  |  |  | 75,956 |  |  |  | 34.7 |
Total net premiums earned |  | $ | 290,689 |  |  |  | 100.0 | % |  | $ | 251,015 |  |  |  | 100.0 | % |  | $ | 218,881 |  |  |  | 100.0 | %

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- Definition Schedule of premiums earned net by geographical segment. + References No definition available. + Details
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