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v3.22.4

Segment Information - Summary of Operating Results by Segment (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) State Subsidiary segment | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Segment Reporting [Abstract] |  |  |
Number of insurance companies | Subsidiary | 12 |  |
Number of states in which company operates | State | 11 |  |
Number of reportable segments | segment | 1 |  |
Segment Reporting Information [Line Items] |  |  |
Net premiums earned | $ 3,952,482 | $ 3,741,948 | $ 3,555,635
Losses and loss adjustment expenses | 3,362,219 | 2,760,155 | 2,395,343
Underwriting expenses | 934,400 | 916,700 | 913,700
Underwriting (loss) gain | (344,100) | 65,000 | 246,600
Net investment income | 168,356 | 129,727 | 134,858
Net realized investment (losses) gains | (488,080) | 111,658 | 85,731
Other income | 10,308 | 10,024 | 8,287
Interest expense | (17,232) | (17,113) | (17,048)
(Loss) income before income taxes | (670,715) | 299,307 | 458,501
Net (loss) income | (512,672) | 247,937 | 374,607
Property & Casualty |  |  |
Segment Reporting Information [Line Items] |  |  |
Net premiums earned | 3,923,642 | 3,712,910 | 3,526,753
Losses and loss adjustment expenses | 3,347,200 | 2,746,300 | 2,381,500
Underwriting expenses | 922,100 | 902,600 | 899,100
Underwriting (loss) gain | (345,700) | 64,000 | 246,200
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net premiums earned | 28,900 | 29,000 | 28,800
Losses and loss adjustment expenses | 15,000 | 13,900 | 13,800
Underwriting expenses | 12,300 | 14,100 | 14,600
Underwriting (loss) gain | $ 1,600 | $ 1,000 | $ 400

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