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v3.25.1

Segment Information - Schedule of Combined Ratio (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Revenue from External Customer [Line Items] |  |
Net premiums earned | $ 1,158,757 | $ 1,050,944
Loss and loss expense incurred | 746,325 | 704,292
Total Insurance Operations |  |
Revenue from External Customer [Line Items] |  |
Net premiums earned | 1,158,757 | 1,050,944
Loss and loss expense incurred | 746,325 | 704,292
Net underwriting expenses incurred | 365,812 | 324,367
Dividends to policyholders | 983 | 3,254
Underwriting income (loss) | $ 45,637 | $ 19,031
Ratio |  |
Loss and loss expense incurred (as a percent) | 64.40% | 67.00%
Net underwriting expenses incurred (as a percent) | 31.60% | 30.90%
Dividends to policyholders (as a percent) | 0.10% | 0.30%
Underwriting income (loss) (as a percent) | 96.10% | 98.20%
Standard Commercial Lines |  |
Revenue from External Customer [Line Items] |  |
Net premiums earned | $ 912,210 | $ 834,110
Loss and loss expense incurred | 581,666 | 555,833
Net underwriting expenses incurred | 296,643 | 264,642
Dividends to policyholders | 983 | 3,254
Underwriting income (loss) | $ 32,918 | $ 10,381
Ratio |  |
Loss and loss expense incurred (as a percent) | 63.80% | 66.70%
Net underwriting expenses incurred (as a percent) | 32.50% | 31.70%
Dividends to policyholders (as a percent) | 0.10% | 0.40%
Underwriting income (loss) (as a percent) | 96.40% | 98.80%
Standard Personal Lines |  |
Revenue from External Customer [Line Items] |  |
Net premiums earned | $ 103,655 | $ 103,846
Loss and loss expense incurred | 76,669 | 84,344
Net underwriting expenses incurred | 24,949 | 24,837
Underwriting income (loss) | $ 2,037 | $ (5,335)
Ratio |  |
Loss and loss expense incurred (as a percent) | 73.90% | 81.20%
Net underwriting expenses incurred (as a percent) | 24.10% | 23.90%
Underwriting income (loss) (as a percent) | 98.00% | 105.10%
E&S Lines |  |
Revenue from External Customer [Line Items] |  |
Net premiums earned | $ 142,892 | $ 112,988
Loss and loss expense incurred | 87,990 | 64,115
Net underwriting expenses incurred | 44,220 | 34,888
Underwriting income (loss) | $ 10,682 | $ 13,985
Ratio |  |
Loss and loss expense incurred (as a percent) | 61.60% | 56.70%
Net underwriting expenses incurred (as a percent) | 30.90% | 30.90%
Underwriting income (loss) (as a percent) | 92.50% | 87.60%

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