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v3.24.0.1

Segment Information - Summary of Operating Results by Segment (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($) State Subsidiary segment | Dec. 31, 2022 USD ($) | Dec. 31, 2021 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 | $ 4,274,378 | $ 3,952,482 | $ 3,741,948
Losses and loss adjustment expenses | 3,517,853 | 3,362,219 | 2,760,155
Underwriting expenses | 988,100 | 934,400 | 916,700
Underwriting (loss) gain | (231,600) | (344,100) | 65,000
Net investment income | 234,630 | 168,356 | 129,727
Net realized investment gains (losses) | 101,014 | (488,080) | 111,658
Other income | 19,609 | 10,308 | 10,024
Interest expense | (24,169) | (17,232) | (17,113)
Income (loss) before income taxes | 99,428 | (670,715) | 299,307
Net income (loss) | 96,336 | (512,672) | 247,937
Property & Casualty |  |  |
Segment Reporting Information [Line Items] |  |  |
Net premiums earned | 4,245,369 | 3,923,642 | 3,712,910
Losses and loss adjustment expenses | 3,502,200 | 3,347,200 | 2,746,300
Underwriting expenses | 973,400 | 922,100 | 902,600
Underwriting (loss) gain | (230,200) | (345,700) | 64,000
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net premiums earned | 29,000 | 28,900 | 29,000
Losses and loss adjustment expenses | 15,700 | 15,000 | 13,900
Underwriting expenses | 14,700 | 12,300 | 14,100
Underwriting (loss) gain | $ (1,400) | $ 1,600 | $ 1,000

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The difference between the price paid by the public and the contract price less the related expenses. A broker-dealer may underwrite a security offering by contracting to buy the issue either at a fixed price or a price based on selling the offering on a best-effort basis. + References No definition available. + Details
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