Note 3 - Loans and Allowance for Credit Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2023	Mar. 31, 2023	Jun. 30, 2023
Impaired Financing Receivable, Interest Income, Cash Basis Method	$ 10	$ 10	$ 558
Impaired Financing Receivable, Recorded Investment			405
Impaired Financing Receivable, Related Allowance			0
Impaired Financing Receivable, Average Recorded Investment	399	405
Impaired Financing Receivable, Interest Income, Accrual Method	10	34
Impaired Financing Receivable, Interest Income, Cash Basis Method		34
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	315	303
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	9	27
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	9	27
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	315	303
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	9	27
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	9	27
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	39	40
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	5
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	5
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	39	40
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	5
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	5
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	18	20
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	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, with No Related Allowance, Average Recorded Investment	18	20
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	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, with No Related Allowance, Average Recorded Investment	27	42
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	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	27	42
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	$ 0	$ 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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