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v3.20.2

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 694,541 | $ 653,620 | $ 1,976,915 | $ 1,928,812
Miscellaneous income | 6,119 | 3,162 | 12,627 | 8,535
Net investment income | 68,185 | 55,826 | 158,596 | 164,949
Net realized and unrealized investment gains (losses) | 7,721 | (2,183) | (24,296) | 15,295
Total Investments revenue | 75,906 | 53,643 | 134,300 | 180,244
Total revenues | 776,566 | 710,425 | 2,123,842 | 2,117,591
Standard Commercial Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 5,521 | 2,782 | 11,107 | 7,544
Total revenues | 563,606 | 517,943 | 1,586,776 | 1,526,538
Standard Commercial Lines [Member] | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 160,937 | 141,182 | 449,162 | 408,706
Standard Commercial Lines [Member] | Workers Compensation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 75,595 | 75,478 | 204,207 | 232,657
Standard Commercial Lines [Member] | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 181,459 | 169,084 | 509,312 | 495,402
Standard Commercial Lines [Member] | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 97,997 | 89,215 | 287,279 | 262,418
Standard Commercial Lines [Member] | Business Owners Policies [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 27,605 | 26,371 | 82,157 | 78,624
Standard Commercial Lines [Member] | Bonds Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 9,226 | 8,990 | 28,075 | 26,861
Standard Commercial Lines [Member] | Other Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 5,266 | 4,841 | 15,477 | 14,326
Standard Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 598 | 380 | 1,520 | 991
Total revenues | 76,574 | 77,118 | 225,257 | 232,149
Standard Personal Lines [Member] | Personal Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 42,458 | 43,226 | 123,134 | 129,777
Standard Personal Lines [Member] | Homeowners [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 31,395 | 31,529 | 94,537 | 95,672
Standard Personal Lines [Member] | Other Personal [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 2,123 | 1,983 | 6,066 | 5,709
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 60,480 | 61,721 | 177,509 | 178,660
Excess And Surplus Operations [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 43,650 | 47,171 | 130,444 | 136,455
Excess And Surplus Operations [Member] | Property Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 16,830 | $ 14,550 | $ 47,065 | $ 42,205

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