Note 3 - Loans and Allowance for Credit Losses - Impaired Loans (Details) $ in Thousands	12 Months Ended
Jun. 30, 2023 USD ($)
Impaired Financing Receivable, Related Allowance	$ 0
Impaired Financing Receivable, Related Allowance	0
Impaired Financing Receivable, Unpaid Principal Balance	558
Impaired Financing Receivable, Recorded Investment	405
Impaired Financing Receivable, Average Recorded Investment	425
Impaired Financing Receivable, Interest Income, Accrual Method	45
Impaired Financing Receivable, Interest Income, Cash Basis Method	45
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, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	306
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	37
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	37
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	404
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	314
Impaired Financing Receivable, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	306
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	37
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	37
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, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	52
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	6
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	6
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	127
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	88
Impaired Financing Receivable, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	52
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	6
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	6
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, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	38
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	2
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	24
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0
Impaired Financing Receivable, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	38
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	2
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, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	29
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, Related Allowance	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	29
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.

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