Note 7 - Fair Value of Assets and Liabilities (Detail) - Financial assets measured at fair value on a recurring basis (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Liabilities:
Derivative payable	$ 464	$ 513
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
U.S. government agencies and corporations	25,922	24,649
Mortgage-backed securities	1,955	2,189
Obligations of states and political subdivisions	122,456	125,875
Preferred stock	188	104
Total securities available for sale	150,521	152,817
Liabilities:
Derivative payable	464	513
Fair Value, Measurements, Recurring [Member]
Assets:
U.S. government agencies and corporations	25,922	24,649
Mortgage-backed securities	1,955	2,189
Obligations of states and political subdivisions	122,456	125,875
Preferred stock	188	104
Total securities available for sale	150,521	152,817
Liabilities:
Derivative payable	$ 464	$ 513

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Bonds or similar securities issued by state, city, or local US governments or the agencies operated by state, city, or local governments. Debt securities issued by state governments may include bond issuances of US state authorities including, for example, but not limited to, housing authorities, dormitory authorities, and general obligations while debt securities issued by political subdivisions of US states would include, for example, debt issuances by county, borough, city, or municipal governments.

+ References

No definition available.

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- Definition

This item represents the amount of preferred stock which the Company has and which is outstanding as of the balance sheet date. A financial instrument in the form of shares.

+ References

No definition available.

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- Definition

This category includes investments in debt securities issued by: (1) the United States Department of the Treasury and backed by the United States government. Such securities primarily consist of treasury bills (short-term maturities - one year or less), treasury notes (intermediate term maturities - two to ten years), and treasury bonds (long-term maturities - ten to thirty years) and (2) US Government Corporations and Agencies.

+ References

No definition available.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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- Definition

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 15

-Paragraph 83

-URI http://asc.fasb.org/extlink&oid=6913464&loc=d3e34841-113949

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 10

-Subparagraph i

-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

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 6

-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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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as available-for-sale.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 15

-IssueDate 2006-05-01

-Chapter 7

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

-URI http://asc.fasb.org/extlink&oid=6517959

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