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v3.21.2

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 767,247 | $ 694,541 | $ 2,232,725 | $ 1,976,915
Miscellaneous income | 4,588 | 6,119 | 14,912 | 12,627
Net investment income | 93,032 | 68,185 | 246,479 | 158,596
Net realized and unrealized investment gains (losses) | 177 | 7,721 | 15,353 | (24,296)
Total Investments revenue | 93,209 | 75,906 | 261,832 | 134,300
Total revenues | 865,044 | 776,566 | 2,509,469 | 2,123,842
Standard Commercial Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 4,168 | 5,521 | 13,670 | 11,107
Total revenues | 623,739 | 563,606 | 1,822,136 | 1,586,776
Standard Commercial Lines | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 111,981 | 97,997 | 320,904 | 287,279
Standard Commercial Lines | Workers Compensation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 78,318 | 75,595 | 230,845 | 204,207
Standard Commercial Lines | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 205,904 | 181,459 | 596,717 | 509,312
Standard Commercial Lines | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 185,610 | 160,937 | 535,519 | 449,162
Standard Commercial Lines | Business Owners Policies [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 23,025 | 27,605 | 80,963 | 82,157
Standard Commercial Lines | Bonds Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 8,850 | 9,226 | 26,436 | 28,075
Standard Commercial Lines | Other Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 5,883 | 5,266 | 17,082 | 15,477
Standard Personal Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 420 | 598 | 1,242 | 1,520
Total revenues | 73,782 | 76,574 | 221,718 | 225,257
Standard Personal Lines | Personal Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 40,575 | 42,458 | 122,977 | 123,134
Standard Personal Lines | Homeowners [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 30,633 | 31,395 | 91,801 | 94,537
Standard Personal Lines | Other Personal [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 2,154 | 2,123 | 5,698 | 6,066
E&S Lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 74,314 | 60,480 | 203,783 | 177,509
E&S Lines | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 52,983 | 43,650 | 144,458 | 130,444
E&S Lines | Property Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 21,331 | $ 16,830 | $ 59,325 | $ 47,065

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