Note 3 - Loans and Allowance for Credit Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2022	Jun. 30, 2023
Impaired Financing Receivable, Unpaid Principal Balance		$ 558
Impaired Financing Receivable, Recorded Investment		405
Impaired Financing Receivable, Related Allowance		0
Impaired Financing Receivable, Average Recorded Investment	$ 410
Impaired Financing Receivable, Interest Income, Accrual Method	14
Impaired Financing Receivable, Interest Income, Cash Basis Method	14
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		404
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		314
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	286
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	10
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	10
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		404
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		314
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	286
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	10
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	10
Commercial Real Estate Portfolio Segment [Member] \| Other Commercial Real Estate Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		127
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		88
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	41
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	3
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	3
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		127
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		88
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	41
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	3
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	3
Residential Portfolio Segment [Member] \| Owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		24
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	21
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		24
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	21
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1
Residential Portfolio Segment [Member] \| Non-owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		3
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		3
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	62
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		3
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		$ 3
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	62
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	$ 0

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
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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-SubTopic 10
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+ References

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-SubTopic 10
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