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v3.20.2

Segment Information (Reconciliation of Segment Results to Income Before Federal Income Tax (Details)) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Investment income | $ 75,906 | $ 53,643 | $ 134,300 | $ 180,244
Interest expense | (7,781) | (7,397) | (23,310) | (26,289)
Corporate expenses | (3,905) | (6,369) | (19,310) | (28,345)
Income before federal income tax | 85,257 | 71,178 | 143,947 | 235,097
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 | 42,718 | 30,016 | 76,574 | 92,974
Standard Personal Lines [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | (14,404) | (631) | (20,342) | 7,074
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | (7,277) | 1,916 | (3,965) | 9,439
Operating Segments [Member] |  |  |  |
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items] |  |  |  |
Total income, before federal income tax all segments | $ 96,943 | $ 84,944 | $ 186,567 | $ 289,731

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