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v3.6.0.2

Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned | $ 235,053 | $ 237,376 | $ 231,456 | $ 221,341 | $ 226,192 | $ 239,234 | $ 213,508 | $ 217,288 | $ 925,226 | $ 896,222 | $ 844,371
Investment income, net of expenses | 28,094 | 27,515 | 27,248 | 27,809 | 27,926 | 25,939 | 25,756 | 24,120 | 110,666 | 103,741 | 87,647
Realized (losses) gains | (52) | 5,092 | 836 | 3,056 | 1,228 | 640 | 166 | 26,327 | 8,932 | 28,361 | 1,357
Other revenue | 3,425 | 3,867 | 3,994 | 6,373 | 3,087 | 3,698 | 3,699 | 2,480 | 17,659 | 12,964 | 9,259
Loss incurred, net | 47,658 | 60,897 | 46,590 | 85,012 | 95,066 | 76,458 | 90,238 | 81,785 | 240,157 | 343,547 | 496,077
Underwriting and other expenses, net | 56,824 | 53,981 | 49,837 | 56,439 | 53,858 | 65,805 | 37,915 | 51,969 | 217,081 | 209,547 |
Loss on debt extinguishment | 0 | 75,223 | 1,868 | 13,440 | 507 | 0 | 0 | 0 | 90,531 | 507 | 837
Provision for income tax | 54,551 | 27,131 | 56,018 | 34,497 | 6,584 | (695,604) | 1,322 | 3,385 | 172,197 | (684,313) | 2,774
Net income | $ 107,487 | $ 56,618 | $ 109,221 | $ 69,191 | $ 102,418 | $ 822,852 | $ 113,654 | $ 133,076 | $ 342,517 | $ 1,172,000 | $ 251,949
Earnings per Share [Abstract] |  |  |  |  |  |  |  |  |  |  |
Basic (in dollars per share) | $ 0.31 | $ 0.16 | $ 0.32 | $ 0.20 | $ 0.30 | $ 2.42 | $ 0.33 | $ 0.39 | $ 1.00 | $ 3.45 | $ 0.74
Diluted (in dollars per share) | $ 0.28 | $ 0.14 | $ 0.26 | $ 0.17 | $ 0.24 | $ 1.78 | $ 0.28 | $ 0.32 | $ 0.86 | $ 2.60 | $ 0.64

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