Note 18 - Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Recognized Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Mortgage servicing rights	$ 1,061	$ 1,313	$ 1,270	$ 1,247
Total financial assets	805,593	752,864
Total financial liabilities	776,957	737,941
Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	26,412	16,475
Fair Value, Inputs, Level 1 [Member] \| Non-Maturity Deposits [Member]
Deposits	509,743	485,561
Fair Value, Inputs, Level 3 [Member]
Loans held for sale	15,301	7,705
Net loans and leases	572,936	554,223
Mortgage servicing rights	1,061	1,313	$ 1,270	$ 1,247
Hedging assets	970	492
Other borrowings	58,692	65,029
Junior subordinated deferrable interest debentures	11,067	8,318
Hedging liabilities	27	86
Fair Value, Inputs, Level 3 [Member] \| Maturity Deposits [Member]
Deposits	197,428	178,947
Fair Value, Inputs Level 2 and Level 3 [Member]
Securities, including FHLB stock	188,913	172,656
Reported Value Measurement [Member]
Total financial assets	804,950	756,728
Total financial liabilities	778,819	744,639
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	26,412	16,475
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Non-Maturity Deposits [Member]
Deposits	509,743	485,561
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale	15,301	7,705
Net loans and leases	572,293	558,087
Mortgage servicing rights	1,061	1,313
Hedging assets	970	492
Other borrowings	58,750	65,443
Junior subordinated deferrable interest debentures	12,908	12,874
Hedging liabilities	27	86
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Maturity Deposits [Member]
Deposits	197,391	180,675
Reported Value Measurement [Member] \| Fair Value, Inputs Level 2 and Level 3 [Member]
Securities, including FHLB stock	$ 188,913	$ 172,656

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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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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Fair value of all derivative assets designated as fair value hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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Fair value of all derivative liabilities designated as fair value hedging instruments.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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Fair value portion of other liabilities.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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