Note 9 - Income Taxes (Detail) - Income Tax Reconciliation (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statutory tax	$ 3,337	$ 2,685	$ 2,246
Effect of state income tax	53	56	46
Tax credits	(250)	(245)	(224)
Other items	24	19	(62)
Total income taxes	2,762	2,063	1,511
Nondeductible interest expense	12	16	20
Nontaxable Interest Income [Member]
Nontaxable income	(314)	(299)	(279)
Bank Owned Insurance Income [Member]
Nontaxable income	$ (100)	$ (169)	$ (236)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

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-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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

-Publisher FASB

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

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-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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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 Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 the differences 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 nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

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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, that is attributable to state and local income tax expense or 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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