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Federal Income Taxes (Reconciliation of Federal Income Tax on Pre-tax Earnings) (Details) (USD $)	3 Months Ended				9 Months Ended				12 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011
Income Tax Disclosure [Abstract]
Tax at statutory rate of 35%	$ 7,110,000		$ (13,119,000)		$ 14,985,000		$ (3,998,000)
Tax-advantaged interest	(3,311,000)		(3,477,000)		(9,970,000)		(10,964,000)
Dividends received deduction	(313,000)		(361,000)		(826,000)		(587,000)
Interim period tax rate adjustment	(1,476,000)	[1]	(3,250,000)	[1]	1,304,000	[1]	0	[1]
Other	30,000		42,000		665,000		(524,000)
Income Tax Expense (Benefit)	2,040,000		(20,165,000)		6,158,000		(16,073,000)
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred tax assets	600,000								600,000
Deferred Tax Assets Operating Loss Carryforwards Purchase Price									4,800,000
Deferred Tax Assets Operating Loss Carryforwards Revised Purchase Price	$ 4,200,000				$ 4,200,000
[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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The acquisition revaluation decrease of the sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

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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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