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v3.5.0.2

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ 542,429 | $ 507,390 | $ 1,596,819 | $ 1,473,822
Net investment income | 33,375 | 32,061 | 95,326 | 91,208
Net realized investment gains | 3,688 | 308 | 2,749 | 15,771
Total investment revenues | 37,063 | 32,369 | 98,075 | 106,979
Other income | 2,199 | 698 | 7,018 | 5,521
Total revenues | 581,691 | 540,457 | 1,701,912 | 1,586,322
Standard Commercial Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 423,511 | 389,990 | 1,241,934 | 1,136,960
Standard Commercial Lines [Member] | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 100,612 | 90,758 | 294,927 | 265,771
Standard Commercial Lines [Member] | Workers Compensation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 78,596 | 74,560 | 229,847 | 213,991
Standard Commercial Lines [Member] | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 133,981 | 123,252 | 391,349 | 357,430
Standard Commercial Lines [Member] | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 74,052 | 68,587 | 217,821 | 199,699
Standard Commercial Lines [Member] | Business Owners' Policies [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 24,461 | 23,726 | 73,016 | 69,603
Standard Commercial Lines [Member] | Bonds Segment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 5,795 | 5,031 | 16,924 | 15,137
Standard Commercial Lines [Member] | Other Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 4,089 | 3,628 | 11,868 | 10,649
Standard Commercial Lines [Member] | Miscellaneous Income [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 1,925 | 448 | 6,182 | 4,680
Standard Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 68,965 | 72,338 | 210,555 | 217,479
Standard Personal Lines [Member] | Miscellaneous Income [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 275 | 250 | 836 | 841
Standard Personal Lines [Member] | Personal Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 34,865 | 36,623 | 106,526 | 110,373
Standard Personal Lines [Member] | Homeowners [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 32,031 | 33,670 | 98,342 | 101,122
Standard Personal Lines [Member] | Other Personal [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 1,794 | 1,795 | 4,851 | 5,143
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 52,152 | 45,760 | 151,348 | 124,904
Excess And Surplus Operations [Member] | Commercial Automobile [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 2,902 | 2,056 | 7,963 | 5,562
Excess And Surplus Operations [Member] | General Liability [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 37,398 | 32,395 | 108,372 | 87,914
Excess And Surplus Operations [Member] | Commercial Property [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | 11,853 | 11,309 | 35,013 | 31,428
Excess And Surplus Operations [Member] | Miscellaneous Income [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total net premiums earned | $ (1) | $ 0 | $ 0 | $ 0

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