Note 17 - Fair Value - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale	$ 169,574	$ 153,116
Derivative liabilities	510
Derivative assets		12
Fair Value, Recurring [Member]
Securities available for sale	169,574	153,116
Equity securities	55	55
Fair value loans	10,358	5,412
Deferred compensation assets	3,990	3,527
Deferred compensation liabilities	3,990	3,527
Derivative liabilities	510
Derivative assets		12
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale
Equity securities	55	55
Fair value loans
Deferred compensation assets	3,990	3,527
Deferred compensation liabilities	3,990	3,527
Derivative liabilities
Derivative assets
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	169,574	153,116
Equity securities
Fair value loans
Deferred compensation assets
Deferred compensation liabilities
Derivative liabilities	510
Derivative assets		12
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale
Equity securities
Fair value loans	10,358	5,412
Deferred compensation assets
Deferred compensation liabilities
Derivative liabilities
Derivative assets
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Securities available for sale	5,034	1,113
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	5,034	1,113
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Securities available for sale	86,878	97,289
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	86,878	97,289
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Securities available for sale		19,960
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale		19,960
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| Mortgage-backed Agency Securities [Member]
Securities available for sale	77,662	34,754
Fair Value, Recurring [Member] \| Mortgage-backed Agency Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale
Fair Value, Recurring [Member] \| Mortgage-backed Agency Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	77,662	34,754
Fair Value, Recurring [Member] \| Mortgage-backed Agency Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale

Fair value portion of deferred compensation assets.

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Fair value portion of deferred compensation liabilities.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
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- Definition

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

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