Note 4 - Loans and Allowance for Credit Losses (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Modifications, Recorded Investment	$ 6,678	$ 3,447
Impaired Loans, Restructured, Nonaccrual Status	988	3,126
Troubled Debt Restructurings During Period	3	3
Financing Receivable Modifications	5,821	3,509
Pledged Financial Instruments, Not Separately Reported, Loans Receivable, for Federal Home Loan Bank Debt	32,084	69,145
Restricted Pledged Loans	32,084	35,894
Construction [Member]
Financing Receivable, Modifications, Recorded Investment		3,126
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	3,068
Commercial [Member]
Financing Receivable, Modifications, Recorded Investment	1,196	321
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 988

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953682-111524

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)(1)(i)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B6

-Subparagraph 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

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph a(2)

-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

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings during the period.

+ References

No definition available.

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- Definition

Recorded investment in impaired loan receivables that have been restructured and are on nonaccrual status as of the balance sheet date.

+ References

No definition available.

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- Definition

The estimated amount of restricted loans due to FHLB borrowing collateral requirements.

+ References

No definition available.

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- Definition

Troubled Debt Restructurings During Period

+ References

No definition available.

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