Federal Income Taxes (Reconciliation of Federal Income Tax on Income at the Corporate Rate to the Effective Tax Rate) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Tax at statutory rate of 35%	$ 13,172	$ 3,990	$ 29,453
Tax-advantaged interest	(13,285)	(14,381)	(15,992)
Dividends received deduction	(1,260)	(870)	(357)
Nonqualified deferred compensation	(262)	7	(273)
Amortization of Intangible Assets	687	0	0
Other	620	(29)	572
Total federal income tax (benefit) expense	$ (328)	$ (11,283)	$ 13,403

Current year tax expense (benefit) related to the Company's deferred compensation plan.

No definition available.

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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 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.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Glossary Income Tax Expense (or Benefit)

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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 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.

+ References

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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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 all other items not otherwise listed in the existing taxonomy.

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