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v3.22.1

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2022 | Mar. 31, 2021
Segment Reporting Information [Line Items] |  |
Total net premiums earned | $ 812,283 | $ 724,960
Miscellaneous income | 1,529 | 4,112
Net investment income | 72,602 | 69,716
Net realized and unrealized investment (losses) gains | (40,352) | 5,119
Total Investments revenue | 32,250 | 74,835
Total revenues | 846,062 | 803,907
Standard Commercial Lines |  |
Segment Reporting Information [Line Items] |  |
Total revenues | 662,570 | 592,848
Standard Commercial Lines | Commercial Property [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 120,062 | 102,810
Standard Commercial Lines | Workers Compensation [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 84,680 | 78,190
Standard Commercial Lines | General Liability [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 216,325 | 193,520
Standard Commercial Lines | Commercial Automobile [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 193,830 | 171,881
Standard Commercial Lines | Business Owners Policies [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 30,044 | 28,627
Standard Commercial Lines | Bonds Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 10,360 | 8,593
Standard Commercial Lines | Other Commercial [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 6,168 | 5,520
Standard Commercial Lines | Miscellaneous income |  |
Segment Reporting Information [Line Items] |  |
Miscellaneous income | 1,101 | 3,707
Standard Personal Lines |  |
Segment Reporting Information [Line Items] |  |
Total revenues | 73,070 | 74,226
Standard Personal Lines | Personal Automobile [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 39,716 | 41,393
Standard Personal Lines | Homeowners [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 31,187 | 30,598
Standard Personal Lines | Other Personal [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 1,739 | 1,830
Standard Personal Lines | Miscellaneous income |  |
Segment Reporting Information [Line Items] |  |
Miscellaneous income | 428 | 405
E&S Lines |  |
Segment Reporting Information [Line Items] |  |
Total revenues | 78,172 | 61,998
E&S Lines | Casualty Insurance Product Line [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 54,624 | 43,833
E&S Lines | Property Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | $ 23,548 | $ 18,165

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