Federal Income Taxes (Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Reconciliation [Abstract]
Income tax expense at statutory rate of 35%	$ 49,204	$ 28,993	$ 36,597
Dividend received deduction	(1,292)	(1,178)	(1,077)
Tax exempt interest	(1,977)	(2,033)	(1,854)
Non deductible gifts	2	7	0
Tax adjustment on foreign currency	245	(24)	(482)
Adjustments pertaining to prior tax years	1,244	1,122	(1,944)
Nondeductible insurance	160	160	160
Nondeductible meals	110	38	30
Amortization of life interest in a trust	116	114	113
Other, net	211	10	123
Income Tax Expense (Benefit)	$ 48,023	$ 27,209	$ 31,666
Statutory Rate	35.00%	35.00%	35.00%

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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