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v3.20.2

Segment Information - Summary of Operating Results by Segment (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 USD ($) State | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) segment Subsidiary State | Sep. 30, 2019 USD ($)
Segment Reporting [Abstract] |  |  |  |
Number of insurance companies | Subsidiary |  |  | 14 |
Number of states in which company operates | State | 11 |  | 11 |
Number of reportable segments | segment |  |  | 1 |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 899,304 | $ 915,012 | $ 2,633,775 | $ 2,674,034
Losses and loss adjustment expenses | 618,657 | 680,928 | 1,765,627 | 1,967,921
Underwriting expenses | 229,100 | 221,300 | 683,100 | 654,200
Underwriting gain (loss) | 51,500 | 12,800 | 185,100 | 51,900
Net investment income | 32,140 | 36,356 | 100,801 | 105,562
Net realized investment gains (losses) | 64,436 | 33,324 | (28,458) | 197,726
Other | 2,894 | 2,603 | 6,810 | 7,203
Interest expense | (4,262) | (4,257) | (12,786) | (12,779)
Pre-tax income | 146,631 | 80,840 | 251,392 | 349,604
Net income | 118,857 | 69,282 | 207,864 | 288,399
Property and Casualty Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 892,000 | 907,900 | 2,612,200 | 2,652,800
Losses and loss adjustment expenses | 614,900 | 677,300 | 1,755,200 | 1,957,400
Underwriting expenses | 225,400 | 217,800 | 672,200 | 643,800
Underwriting gain (loss) | 51,700 | 12,800 | 184,800 | 51,600
Other Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,300 | 7,100 | 21,600 | 21,200
Losses and loss adjustment expenses | 3,800 | 3,600 | 10,400 | 10,500
Underwriting expenses | 3,700 | 3,500 | 10,900 | 10,400
Underwriting gain (loss) | $ (200) | $ 0 | $ 300 | $ 300

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