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v3.19.2

Segment Information (Income Before and After Federal Income Tax) (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] |  |  |  |
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 income, before federal income tax | 62,532 | 43,901 | 126,601 | 76,583
Tax on investment income | 11,729 | 7,617 | 23,849 | 12,843
Total investment income, after federal income tax | 50,803 | 36,284 | 102,752 | 63,740
Standard Commercial Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | 37,143 | 41,016 | 62,958 | 47,820
Underwriting gain (loss), after federal income tax | $ 29,343 | $ 32,403 | $ 49,737 | $ 37,778
Combined ratio | 92.70% | 91.40% | 93.70% | 94.90%
ROE Contribution | 5.90% | 7.80% | 5.20% | 4.50%
Standard Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | $ 4,538 | $ 4,805 | $ 7,705 | $ 3,299
Underwriting gain (loss), after federal income tax | $ 3,585 | $ 3,796 | $ 6,087 | $ 2,606
Combined ratio | 94.10% | 93.70% | 95.00% | 97.80%
ROE Contribution | 0.70% | 0.90% | 0.60% | 0.30%
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | $ 2,944 | $ (7,789) | $ 7,523 | $ (8,354)
Underwriting gain (loss), after federal income tax | $ 2,326 | $ (6,154) | $ 5,943 | $ (6,600)
Combined ratio | 95.00% | 114.70% | 93.60% | 107.90%
ROE Contribution | 0.50% | (1.50%) | 0.60% | (0.80%)
Investments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
ROE Contribution | 9.60% | 9.00% | 9.20% | 8.60%

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