Note 4 - Loans and Allowance for Loan Losses (Details Textual)	3 Months Ended
Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Court Order [Member]
Troubled Debt Restructurings During Period	1
Under-market Modification to Payment Terms and Extended Maturity Date [Member]
Troubled Debt Restructurings During Period	2	5
Residential Real Estate Included in OREO [Member]
Real Estate Acquired Through Foreclosure	$ 0		$ 0
Restructured Loans [Member]
Financing Receivable, Modifications, Recorded Investment	19,645,000		15,712,000
Impaired Loans, Restructured, Nonaccrual Status	12,114,000		7,464,000
Three Loans [Member]
Financing Receivable, Modifications, Recorded Investment	$ 4,757,000
Five Loans [Member]
Financing Receivable, Modifications, Recorded Investment		$ 1,736,000
Troubled Debt Restructurings During Period	3
Loans and Leases Receivable, Nonaccrual, Commitment to Lend	$ 0		0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	$ 0		0
Loans Receivable Held-for-sale, Amount	0		0
Mortgage Loans in Process of Foreclosure, Amount	0		0
Financing Receivable, Modifications, Recorded Investment	19,645,000		15,712,000
Other Real Estate	8,438,000		9,264,000
Other Real Estate, Reserve	$ 2,102,000		$ 1,986,000

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=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and 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=66008989&loc=SL6953682-111524

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- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL49126937-111524

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

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
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The sum of the carrying amounts, 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 related debt obligations, primarily secured borrowings and repurchase agreements, and for which the transferees are 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
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-SubTopic 30
-Section 50
-Paragraph 1A
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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04(c)(Schedule III))
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans on nonaccrual status.

+ References

No definition available.

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- Definition

The reserve account relating to other real estate.

+ References

No definition available.

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- Definition

Number of troubled debt restructurings during period.

+ References

No definition available.

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