Note 4 - Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available for sale	$ 118,564	$ 107,592
Fair Value, Recurring [Member]
Securities available for sale	118,564	107,592
Equity securities	127	167
Mortgage loan commitments	266	14
Total	118,957	107,773
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Equity securities	0	0
Mortgage loan commitments	0	0
Total	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	118,564	107,592
Equity securities	127	167
Mortgage loan commitments	266	14
Total	118,957	107,773
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Equity securities	0	0
Mortgage loan commitments	0	0
Total	$ 0	$ 0

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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