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v3.19.3.a.u2

Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned | $ 266,267 | $ 267,857 | $ 247,102 | $ 249,762 | $ 245,665 | $ 250,426 | $ 246,964 | $ 232,107 | $ 1,030,988 | $ 975,162 | $ 934,747
Investment income, net of expenses | 41,322 | 42,715 | 42,423 | 40,585 | 38,328 | 36,380 | 34,502 | 32,121 | 167,045 | 141,331 | 120,871
Realized (losses) gains | 1,320 | 4,205 | 307 | (526) | (241) | 1,114 | (1,897) | (329) | 5,306 | (1,353) | 231
Other revenue | 2,717 | 3,606 | 2,485 | 1,830 | 1,881 | 2,525 | 2,431 | 1,871 | 10,638 | 8,708 | 10,205
Loss incurred, net | 23,690 | 33,985 | 21,836 | 39,064 | 27,685 | (1,518) | (13,455) | 23,850 | 118,575 | 36,562 | 53,709
Underwriting and other expenses, net | 65,227 | 61,278 | 59,270 | 61,650 | 63,239 | 60,069 | 57,933 | 61,895 | 247,425 | 243,136 |
Loss on debt extinguishment |  |  |  |  |  |  |  |  | 0 | 0 | 65
Provision for income tax | 45,599 | 46,186 | 43,433 | 38,996 | 36,963 | 49,994 | 50,708 | 36,388 | 174,214 | 174,053 | 428,735
Net income | $ 177,110 | $ 176,934 | $ 167,778 | $ 151,941 | $ 157,746 | $ 181,900 | $ 186,814 | $ 143,637 | $ 673,763 | $ 670,097 | $ 355,761
Earnings per Share [Abstract] |  |  |  |  |  |  |  |  |  |  |
Basic (in dollars per share) | $ 0.51 | $ 0.50 | $ 0.47 | $ 0.43 | $ 0.44 | $ 0.50 | $ 0.51 | $ 0.39 | $ 1.91 | $ 1.83 | $ 0.98
Diluted (in dollars per share) | $ 0.49 | $ 0.49 | $ 0.46 | $ 0.42 | $ 0.43 | $ 0.49 | $ 0.49 | $ 0.38 | $ 1.85 | $ 1.78 | $ 0.95

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