Note 11 - Fair Value of Financial Instruments and Fair Value Measurements - Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets
Investment Securities Available for Sale	$ 338,249	$ 323,658
Reported Value Measurement [Member]
Assets
Cash and Short-Term Investments	31,600	75,167
Investment Securities Available for Sale	338,249	323,658
Federal Home Loan Bank Stock	3,255	3,010
Loans, Net	761,639	744,999
Bank-Owned Life Insurance	15,823	15,419
Liabilities
Deposits	1,020,263	1,044,357
Subordinated Debentures	24,229	24,229
Other Borrowed Money	56,000	46,000
Estimate of Fair Value Measurement [Member]
Assets
Cash and Short-Term Investments	31,600	75,167
Investment Securities Available for Sale	338,249	323,658
Federal Home Loan Bank Stock	3,255	3,010
Loans, Net	761,831	745,240
Bank-Owned Life Insurance	15,823	15,419
Liabilities
Deposits	1,020,647	1,045,726
Subordinated Debentures	24,229	24,229
Other Borrowed Money	56,251	46,232
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets
Cash and Short-Term Investments	31,600	75,167
Investment Securities Available for Sale
Federal Home Loan Bank Stock	3,255	3,010
Loans, Net
Bank-Owned Life Insurance	15,823	15,419
Liabilities
Deposits	673,468	677,129
Subordinated Debentures
Other Borrowed Money
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets
Cash and Short-Term Investments
Investment Securities Available for Sale	338,019	323,082
Federal Home Loan Bank Stock
Loans, Net	755,385	738,288
Bank-Owned Life Insurance
Liabilities
Deposits	347,179	368,597
Subordinated Debentures	24,229	24,229
Other Borrowed Money	56,251	46,232
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets
Cash and Short-Term Investments
Investment Securities Available for Sale	230	576
Federal Home Loan Bank Stock
Loans, Net	6,446	6,952
Bank-Owned Life Insurance
Liabilities
Deposits
Subordinated Debentures
Other Borrowed Money

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ 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 210.9-03.13(3)(a))
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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75030709&loc=d3e39828-111592

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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