Note 2 - INVESTMENT SECURITIES - Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2023	Sep. 30, 2023
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 180	$ 180
Balance, ending		180
Balance, ending		989
Municipal securities.
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Beginning balance	180	180
Balance, ending		180
Other securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Balance, ending		989
Corporate securities
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Provision for credit loss expense	$ 989	989
Balance, ending		$ 989

Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) transferred into available-for-sale out of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 8B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-8B

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