Note 9 - Federal Income Taxes (Detail) - Reconciliation of the Difference between Federal Income Tax Expense and the Federal Statutory Tax Rate Amount (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Tax at statutory rate	$ 5,177	$ 2,610	$ 1,846
Effect of tax-exempt interest	(479)	(443)	(489)
Deferred tax valuation allowance	0	0	485
Other	(442)	(333)	(330)
Federal income taxes	4,256	1,834	1,512
Effective tax rate	29.00%	25.00%	29.00%
Federal Reconcilliation [Member]
Federal income taxes	$ 4,256	$ 1,834	$ 1,512

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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The sum of domestic current and deferred income tax expense or benefit attributable 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 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 changes in the valuation allowance for deferred tax assets in the period.

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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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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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