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v3.24.2

Segment Information - Schedule of Revenue by Segment (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | $ 1,080,231 | $ 942,150 | $ 2,131,175 | $ 1,844,486
Miscellaneous income | 5,835 | 6,104 | 13,636 | 8,738
Net investment income earned | 108,642 | 97,696 | 216,491 | 189,202
Net realized and unrealized investment gains (losses) | 1,297 | (5,426) | (338) | (2,082)
Total Investments revenue | 109,939 | 92,270 | 216,153 | 187,120
Total revenues | 1,196,005 | 1,040,524 | 2,360,964 | 2,040,344
Standard Commercial Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 858,707 | 768,277 | 1,699,951 | 1,502,073
Standard Commercial Lines | General liability |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 280,097 | 254,510 | 553,512 | 497,859
Standard Commercial Lines | Commercial automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 260,652 | 225,067 | 512,372 | 442,438
Standard Commercial Lines | Commercial property |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 168,511 | 141,348 | 330,064 | 276,640
Standard Commercial Lines | Workers compensation |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 82,316 | 88,746 | 170,093 | 172,930
Standard Commercial Lines | Businessowners' policies |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 41,641 | 34,385 | 81,562 | 67,556
Standard Commercial Lines | Bonds |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 12,468 | 11,619 | 24,556 | 23,016
Standard Commercial Lines | Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 7,808 | 7,034 | 15,444 | 13,885
Standard Commercial Lines | Miscellaneous income |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 5,214 | 5,568 | 12,348 | 7,749
Standard Personal Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 107,015 | 87,706 | 211,502 | 170,029
Standard Personal Lines | Miscellaneous income |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 594 | 536 | 1,235 | 989
Standard Personal Lines | Personal automobile |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 57,544 | 48,230 | 114,504 | 93,144
Standard Personal Lines | Homeowners |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 46,055 | 36,902 | 90,168 | 71,915
Standard Personal Lines | Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 2,822 | 2,038 | 5,595 | 3,981
E&S Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 120,344 | 92,271 | 233,358 | 181,122
E&S Lines | Miscellaneous income |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 27 | 0 | 53 | 0
E&S Lines | Casualty lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | 73,887 | 62,151 | 145,525 | 122,968
E&S Lines | Property lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned: | $ 46,430 | $ 30,120 | $ 87,780 | $ 58,154

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