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v3.19.2

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 642,619 | $ 604,836 | $ 1,275,192 | $ 1,196,664
Miscellaneous income | 3,053 | 3,179 | 5,373 | 5,358
Net investment income | 58,505 | 45,553 | 109,123 | 88,784
Net realized and unrealized investment gains (losses) | 4,027 | (1,652) | 17,478 | (12,201)
Total investment revenues | 62,532 | 43,901 | 126,601 | 76,583
Total revenues | 708,204 | 651,916 | 1,407,166 | 1,278,605
Standard Commercial Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 2,718 | 2,882 | 4,762 | 4,708
Total revenues | 509,367 | 478,894 | 1,008,595 | 946,084
Standard Commercial Lines [Member] | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 136,338 | 122,104 | 267,524 | 240,335
Standard Commercial Lines [Member] | Workers Compensation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 78,464 | 80,021 | 157,179 | 158,844
Standard Commercial Lines [Member] | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 164,793 | 153,002 | 326,318 | 302,831
Standard Commercial Lines [Member] | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 87,136 | 82,162 | 173,203 | 162,488
Standard Commercial Lines [Member] | Business Owners' Policies [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 26,172 | 25,829 | 52,253 | 51,420
Standard Commercial Lines [Member] | Bonds Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 8,967 | 8,335 | 17,871 | 16,469
Standard Commercial Lines [Member] | Other Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 4,779 | 4,559 | 9,485 | 8,989
Standard Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 335 | 297 | 611 | 649
Total revenues | 77,448 | 75,974 | 155,031 | 150,582
Standard Personal Lines [Member] | Personal Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 43,388 | 41,810 | 86,551 | 82,252
Standard Personal Lines [Member] | Homeowners [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 32,013 | 32,223 | 64,143 | 64,424
Standard Personal Lines [Member] | Other Personal [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 1,712 | 1,644 | 3,726 | 3,257
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Miscellaneous income | 0 | 0 | 0 | 1
Total revenues | 58,857 | 53,147 | 116,939 | 105,356
Excess And Surplus Operations [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 44,756 | 39,379 | 89,284 | 77,919
Excess And Surplus Operations [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 14,101 | $ 13,768 | $ 27,655 | $ 27,436

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