Reportable Segments (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) Segment	Mar. 31, 2015 USD ($)
Reportable Segments [Abstract]
Number of reportable segments \| Segment	2
Segment Reporting Information [Line Items]
Net Premiums Earned	$ 66,909	$ 66,446
Reconciliation from segment totals to consolidated [Abstract]
Income before federal income taxes	21,438	9,291
Reportable Segments [Member]
Segment Reporting Information [Line Items]
Direct and Assumed Premium Written	96,153	96,980
Net Premiums Earned	66,909	66,446
Segment Profit (Loss)	13,199	6,924
Reconciliation from segment totals to consolidated [Abstract]
Segment profit	13,199	6,924
Reportable Segments [Member] \| Property and Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Direct and Assumed Premium Written	93,088	90,513
Net Premiums Earned	63,428	59,284
Segment Profit (Loss)	13,744	6,324
Reconciliation from segment totals to consolidated [Abstract]
Segment profit	13,744	6,324
Reportable Segments [Member] \| Reinsurance [Member]
Segment Reporting Information [Line Items]
Direct and Assumed Premium Written	3,065	6,467
Net Premiums Earned	3,481	7,162
Segment Profit (Loss)	(545)	600
Reconciliation from segment totals to consolidated [Abstract]
Segment profit	(545)	600
Segment Reconciling Items [Member]
Reconciliation from segment totals to consolidated [Abstract]
Net investment income	3,440	2,815
Net realized gains on investments	9,012	3,743
Corporate expenses and other	$ (4,213)	$ (4,191)

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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