Note 9 - Federal Income Taxes (Details) - 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, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of the Difference between Federal Income Tax Expense and the Federal Statutory Tax Rate Amount [Abstract]
Tax at statutory rate	$ 6,079	$ 5,177	$ 2,610
Effect of tax-exempt interest	(669)	(479)	(443)
Other	(276)	(442)	(333)
Federal income taxes	$ 5,134	$ 4,256	$ 1,834
Effective tax rate	30.00%	29.00%	25.00%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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Amount of current and deferred income tax expense (benefit) attributable to income (loss) from continuing domestic operations within the country of domicile of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Glossary Income Tax Expense (or Benefit)

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-Publisher FASB

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-Subparagraph (SX 210.4-08.(h)(1))

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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