Note 11 - Federal Income Taxes (Details) - Effective Income Tax Rate Reconciliation (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Income Tax Rate Reconciliation [Abstract]
Tax at statutory rate (35%)	$ 8,819,000	$ 8,794,000	$ 6,360,000
Increase (decrease) from
Tax-exempt interest	(621,000)	(347,000)	(486,000)
Bank owned life insurance	(415,000)	(465,000)	(535,000)
Other	82,000	110,000	297,000
Tax expense	$ 7,865,000us-gaap_IncomeTaxExpenseBenefit	$ 8,092,000us-gaap_IncomeTaxExpenseBenefit	$ 5,636,000us-gaap_IncomeTaxExpenseBenefit

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Amount of the difference between reported income tax expense (benefit) and expected tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from bank owned life insurance that is exempt from income taxes.

+ References

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-Name Accounting Standards Codification

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-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

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-Publisher SEC

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-Number 210

-Section 08

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-Subparagraph 2

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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 other adjustments.

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