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v3.23.2

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 942,150 | $ 834,439 | $ 1,844,486 | $ 1,646,722
Other income | 6,104 | 3,037 | 8,738 | 4,566
Net investment income earned | 97,696 | 70,222 | 189,202 | 142,824
Net realized and unrealized investment gains (losses) | (5,426) | (42,880) | (2,082) | (83,232)
Total Investments revenue | 92,270 | 27,342 | 187,120 | 59,592
Total revenues | 1,040,524 | 864,818 | 2,040,344 | 1,710,880
Standard Commercial Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 768,277 | 682,833 | 1,502,073 | 1,345,403
Standard Commercial Lines | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 254,510 | 226,285 | 497,859 | 442,610
Standard Commercial Lines | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 225,067 | 198,381 | 442,438 | 392,211
Standard Commercial Lines | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 141,348 | 123,562 | 276,640 | 243,624
Standard Commercial Lines | Workers Compensation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 88,746 | 83,502 | 172,930 | 168,182
Standard Commercial Lines | Business Owners Policies [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 34,385 | 31,508 | 67,556 | 61,552
Standard Commercial Lines | Bonds Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 11,619 | 10,682 | 23,016 | 21,042
Standard Commercial Lines | Other Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 7,034 | 6,317 | 13,885 | 12,485
Standard Commercial Lines | Miscellaneous income |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Other income | 5,568 | 2,596 | 7,749 | 3,697
Standard Personal Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 87,706 | 73,779 | 170,029 | 146,849
Standard Personal Lines | Personal Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 48,230 | 39,952 | 93,144 | 79,668
Standard Personal Lines | Homeowners [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 36,902 | 31,630 | 71,915 | 62,817
Standard Personal Lines | Other Personal [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 2,038 | 1,756 | 3,981 | 3,495
Standard Personal Lines | Miscellaneous income |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Other income | 536 | 441 | 989 | 869
E&S Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 92,271 | 80,864 | 181,122 | 159,036
E&S Lines | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 62,151 | 56,041 | 122,968 | 110,665
E&S Lines | Property Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 30,120 | $ 24,823 | $ 58,154 | $ 48,371

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