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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Summary of Significant Accounting Policies (AOCI) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net investment gains (losses)									$ 11,755	$ 8,958	$ 14,541
Earnings before federal income taxes									157,521	141,697	140,581
Federal income taxes									51,933us-gaap_IncomeTaxExpenseBenefit	45,450us-gaap_IncomeTaxExpenseBenefit	48,023us-gaap_IncomeTaxExpenseBenefit
Net Earnings	28,113us-gaap_NetIncomeLoss	28,466us-gaap_NetIncomeLoss	29,183us-gaap_NetIncomeLoss	19,826us-gaap_NetIncomeLoss	27,842us-gaap_NetIncomeLoss	24,782us-gaap_NetIncomeLoss	26,991us-gaap_NetIncomeLoss	16,632us-gaap_NetIncomeLoss	105,588us-gaap_NetIncomeLoss	96,247us-gaap_NetIncomeLoss	92,558us-gaap_NetIncomeLoss
Accumulated other comprehensive income (loss) [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other net investment gains (losses)									7,843	4,923	7,308
Net OTTI losses recognized in earnings									150	213	378
Earnings before federal income taxes									7,693	4,710	6,930
Federal income taxes									2,693	1,649	2,426
Net Earnings									$ 5,000	$ 3,061	$ 4,504