Income Taxes (Details 1) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of federal income tax rate
Income (loss) before income taxes	$ 27,858,260	$ (6,739,313)	$ 9,844,149
Computed "expected" taxes (benefit)	9,750,391	(2,358,760)	3,445,452
Tax-exempt interest	(5,824,281)	(6,038,463)	(6,183,795)
Proration	869,551	905,326	923,071
Other, net	(30,021)	299,631	192,242
Federal income tax (benefit) provision	$ 4,765,640	$ (7,192,266)	$ (1,623,030)

Income tax reconciliation proration.

No definition available.

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- Definition

The sum of domestic current and deferred income tax expense or benefit attributable to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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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.

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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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 income that is exempt from income taxes under enacted tax laws.

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