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Federal Income Taxes (Reconciliation of Federal Income Tax on Pre-tax Earnings from Continuing Operations at the Corporate Rate to the Effective Rate) (Details) (USD $) In Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Federal Income Taxes [Abstract]
Tax at statutory rate of 35%	$ (14,290)		$ 7,721		$ (4,142)		$ 18,394
Tax-advantaged interest	(4,090)		(4,479)		(12,898)		(14,224)
Dividends received deduction	(280)		(67)		(546)		(250)
Interim period tax rate adjustment	(3,250)	[1]	(580)	[1]	0	[1]	606	[1]
Other	574		634		1,369		2,514
Total federal income tax (benefit) expense	$ (21,336)		$ 3,229		$ (16,217)		$ 7,040
[1] 1During Third Quarter 2011, we recorded year-to-date taxes using the actual effective tax rate as opposed to the estimated full-year effective tax rate that was used in previous quarters.

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- Definition

The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting 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 recording year-to-date taxes using the actual effective tax rate as opposed to the estimated full-year effective tax rate.

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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 attributable to investment income that is tax advantaged. Tax advantaged investment securities generally are, by statute, tax-reduced, tax-deferred, or tax-free.

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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 attributable to the deduction for dividends paid or received under enacted tax laws.

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