Consolidation and Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net investment gains (losses)	$ 1,443	$ 2,275	$ 11,549	$ 5,582
Net OTTI losses recognized in earnings	(1,945)	0	(7,847)	0
Earnings before Federal income taxes	24,992	44,734	117,727	118,650
Federal income taxes	5,003	9,093	23,844	23,668
Net earnings	19,989	35,641	93,883	94,982
Unrealized Gains and Losses on Available-for-sale Securities \| Amount Reclassified From Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net investment gains (losses)	198	1,185	2,465	3,206
Net OTTI losses recognized in earnings	(1,945)	0	(7,847)	0
Earnings before Federal income taxes	(1,747)	1,185	(5,382)	3,206
Federal income taxes	(367)	249	(1,130)	673
Net earnings	$ (1,380)	$ 936	$ (4,252)	$ 2,533

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.

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