Note 4 - Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available for sale	$ 284,648	$ 285,765
Fair Value, Recurring [Member]
Securities available for sale	284,648	285,765
Equity securities	217	248
Mortgage loan commitments	(131)	26
Total	284,734	286,039
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	284,648	285,765
Equity securities	217	248
Mortgage loan commitments	(131)	26
Total	284,734	286,039
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

The fair value portion of mortgage loan commitments assets (liabilities).

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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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
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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), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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