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v3.21.1

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Segment Reporting Information [Line Items] |  |
Total net premiums earned | $ 724,960 | $ 651,703
Miscellaneous income | 4,112 | 1,825
Net investment income | 69,716 | 55,967
Net realized and unrealized investment gains (losses) | 5,119 | (44,666)
Total Investments revenue | 74,835 | 11,301
Total revenues | 803,907 | 664,829
Standard Commercial Lines |  |
Segment Reporting Information [Line Items] |  |
Miscellaneous income | 3,707 | 1,391
Total revenues | 592,848 | 517,971
Standard Commercial Lines | Commercial Property [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 102,810 | 93,869
Standard Commercial Lines | Workers Compensation [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 78,190 | 66,706
Standard Commercial Lines | General Liability [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 193,520 | 164,580
Standard Commercial Lines | Commercial Automobile [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 171,881 | 149,690
Standard Commercial Lines | Business Owners Policies [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 28,627 | 27,036
Standard Commercial Lines | Bonds Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 8,593 | 9,639
Standard Commercial Lines | Other Commercial [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 5,520 | 5,060
Standard Personal Lines |  |
Segment Reporting Information [Line Items] |  |
Miscellaneous income | 405 | 434
Total revenues | 74,226 | 76,562
Standard Personal Lines | Personal Automobile [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 41,393 | 42,487
Standard Personal Lines | Homeowners [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 30,598 | 31,490
Standard Personal Lines | Other Personal [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 1,830 | 2,151
E&S Lines |  |
Segment Reporting Information [Line Items] |  |
Total revenues | 61,998 | 58,995
E&S Lines | Casualty Insurance Product Line [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | 43,833 | 44,072
E&S Lines | Property Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Total net premiums earned | $ 18,165 | $ 14,923

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