Note 4 - Loans Receivable and Credit Disclosures - Impaired Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)
Impaired financing receivable with no related allowance, recorded investment	$ 13,987
Impaired financing receivable with no related allowance, unpaid principal balance	14,837
Impaired financing receivable, with no related allowance, average recorded investment	4,804
Impaired financing receivable, with no related allowance, interest income, accrual method	91
Impaired financing receivable with related allowance, recorded investment	399
Impaired financing receivable with related allowance, unpaid principal balance	436
Impaired financing receivable, related allowance	95
Impaired financing receivable, with related allowance, average recorded investment	8,201
Impaired financing receivable, with related allowance, interest income, accrual method	2
Impaired financing receivable, recorded investment	14,386
Impaired financing receivable, unpaid principal balance	15,273
Impaired financing receivable, average recorded investment	13,005
Impaired financing receivable, interest income, accrual method	93
Construction Real Estate [Member]
Impaired financing receivable with no related allowance, recorded investment	0
Impaired financing receivable with no related allowance, unpaid principal balance	0
Impaired financing receivable, with no related allowance, average recorded investment	0
Impaired financing receivable, with no related allowance, interest income, accrual method	0
Impaired financing receivable with related allowance, recorded investment	0
Impaired financing receivable with related allowance, unpaid principal balance	0
Impaired financing receivable, related allowance	0
Impaired financing receivable, with related allowance, average recorded investment	0
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	0
Impaired financing receivable, unpaid principal balance	0
Impaired financing receivable, average recorded investment	0
Impaired financing receivable, interest income, accrual method	0
Family Residential Real Estate 1-4 [Member]
Impaired financing receivable with no related allowance, recorded investment	687
Impaired financing receivable with no related allowance, unpaid principal balance	721
Impaired financing receivable, with no related allowance, average recorded investment	715
Impaired financing receivable, with no related allowance, interest income, accrual method	70
Impaired financing receivable with related allowance, recorded investment	118
Impaired financing receivable with related allowance, unpaid principal balance	123
Impaired financing receivable, related allowance	10
Impaired financing receivable, with related allowance, average recorded investment	188
Impaired financing receivable, with related allowance, interest income, accrual method	1
Impaired financing receivable, recorded investment	805
Impaired financing receivable, unpaid principal balance	844
Impaired financing receivable, average recorded investment	903
Impaired financing receivable, interest income, accrual method	71
Multifamily [Member]
Impaired financing receivable with no related allowance, recorded investment	0
Impaired financing receivable with no related allowance, unpaid principal balance	0
Impaired financing receivable, with no related allowance, average recorded investment	0
Impaired financing receivable, with no related allowance, interest income, accrual method	0
Impaired financing receivable with related allowance, recorded investment	0
Impaired financing receivable with related allowance, unpaid principal balance	0
Impaired financing receivable, related allowance	0
Impaired financing receivable, with related allowance, average recorded investment	0
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	0
Impaired financing receivable, unpaid principal balance	0
Impaired financing receivable, average recorded investment	0
Impaired financing receivable, interest income, accrual method	0
Commercial Real Estate Portfolio Segment [Member]
Impaired financing receivable with no related allowance, recorded investment	12,853
Impaired financing receivable with no related allowance, unpaid principal balance	13,578
Impaired financing receivable, with no related allowance, average recorded investment	3,391
Impaired financing receivable, with no related allowance, interest income, accrual method	0
Impaired financing receivable with related allowance, recorded investment	0
Impaired financing receivable with related allowance, unpaid principal balance	0
Impaired financing receivable, related allowance	0
Impaired financing receivable, with related allowance, average recorded investment	7,667
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	12,853
Impaired financing receivable, unpaid principal balance	13,578
Impaired financing receivable, average recorded investment	11,058
Impaired financing receivable, interest income, accrual method	0
Agriculture Real Estate [Member]
Impaired financing receivable with no related allowance, recorded investment	165
Impaired financing receivable with no related allowance, unpaid principal balance	194
Impaired financing receivable, with no related allowance, average recorded investment	319
Impaired financing receivable, with no related allowance, interest income, accrual method	14
Impaired financing receivable with related allowance, recorded investment	0
Impaired financing receivable with related allowance, unpaid principal balance	0
Impaired financing receivable, related allowance	0
Impaired financing receivable, with related allowance, average recorded investment	0
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	165
Impaired financing receivable, unpaid principal balance	194
Impaired financing receivable, average recorded investment	319
Impaired financing receivable, interest income, accrual method	14
Commercial Portfolio Segment [Member]
Impaired financing receivable with no related allowance, recorded investment	200
Impaired financing receivable with no related allowance, unpaid principal balance	249
Impaired financing receivable, with no related allowance, average recorded investment	227
Impaired financing receivable, with no related allowance, interest income, accrual method	6
Impaired financing receivable with related allowance, recorded investment	0
Impaired financing receivable with related allowance, unpaid principal balance	0
Impaired financing receivable, related allowance	0
Impaired financing receivable, with related allowance, average recorded investment	35
Impaired financing receivable, with related allowance, interest income, accrual method	1
Impaired financing receivable, recorded investment	200
Impaired financing receivable, unpaid principal balance	249
Impaired financing receivable, average recorded investment	262
Impaired financing receivable, interest income, accrual method	7
Agriculture [Member]
Impaired financing receivable with no related allowance, recorded investment	78
Impaired financing receivable with no related allowance, unpaid principal balance	88
Impaired financing receivable, with no related allowance, average recorded investment	147
Impaired financing receivable, with no related allowance, interest income, accrual method	0
Impaired financing receivable with related allowance, recorded investment	264
Impaired financing receivable with related allowance, unpaid principal balance	294
Impaired financing receivable, related allowance	68
Impaired financing receivable, with related allowance, average recorded investment	292
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	342
Impaired financing receivable, unpaid principal balance	382
Impaired financing receivable, average recorded investment	439
Impaired financing receivable, interest income, accrual method	0
Consumer and Other [Member]
Impaired financing receivable with no related allowance, recorded investment	4
Impaired financing receivable with no related allowance, unpaid principal balance	7
Impaired financing receivable, with no related allowance, average recorded investment	5
Impaired financing receivable, with no related allowance, interest income, accrual method	1
Impaired financing receivable with related allowance, recorded investment	17
Impaired financing receivable with related allowance, unpaid principal balance	19
Impaired financing receivable, related allowance	17
Impaired financing receivable, with related allowance, average recorded investment	19
Impaired financing receivable, with related allowance, interest income, accrual method	0
Impaired financing receivable, recorded investment	21
Impaired financing receivable, unpaid principal balance	26
Impaired financing receivable, average recorded investment	24
Impaired financing receivable, interest income, accrual method	$ 1

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-17

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

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-Publisher FASB
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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