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v3.25.1

Segment Information - Schedule of Return on Equity (Details) | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Segment Reporting Information [Line Items] |  |
ROE | 14.40% | 11.50%
Operating Segments | Total Insurance Operations |  |
Segment Reporting Information [Line Items] |  |
ROE | 4.80% | 2.20%
Operating Segments | Standard Commercial Lines |  |
Segment Reporting Information [Line Items] |  |
ROE | 3.50% | 1.20%
Operating Segments | Standard Personal Lines |  |
Segment Reporting Information [Line Items] |  |
ROE | 0.20% | (0.60%)
Operating Segments | E&S Lines |  |
Segment Reporting Information [Line Items] |  |
ROE | 1.10% | 1.60%
Operating Segments | Investments |  |
Segment Reporting Information [Line Items] |  |
Net investment income earned | 12.80% | 12.30%
Net realized and unrealized investment gains (losses) | 0.00% | (0.20%)
ROE | 12.80% | 12.10%
Other |  |
Segment Reporting Information [Line Items] |  |
ROE | (3.20%) | (2.80%)

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