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v3.20.4

Segment Information (Reconciliation of Segment Results to Income from Continuing Operations, before Federal Income Tax) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total investment revenues |  |  |  |  |  |  |  |  | $ 222,890 | $ 236,965 | $ 140,413
Interest expense |  |  |  |  |  |  |  |  | (30,839) | (33,668) | (24,419)
Corporate expenses |  |  |  |  |  |  |  |  | (25,412) | (30,900) | (25,446)
Income before federal income tax | $ 159,041 | $ 85,257 | $ 42,693 | $ 15,997 | $ 101,293 | $ 71,178 | $ 90,225 | $ 73,694 | 302,988 | 336,390 | 211,721
Standard Commercial Lines [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |  |  |  |  |  |  |
Underwriting gain (loss), before federal income tax |  |  |  |  |  |  |  |  | 151,731 | 145,990 | 109,104
Standard Personal Lines |  |  |  |  |  |  |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |  |  |  |  |  |  |
Underwriting gain (loss), before federal income tax |  |  |  |  |  |  |  |  | (15,508) | 8,260 | 12,764
E&S Lines [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |  |  |  |  |  |  |
Underwriting gain (loss), before federal income tax |  |  |  |  |  |  |  |  | 126 | 9,743 | (695)
Operating Segments [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total all segments |  |  |  |  |  |  |  |  | $ 359,239 | $ 400,958 | $ 261,586

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