Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020
Impaired Financing Receivable, Related Allowance	$ 8		$ 34
Impaired Financing Receivable, Unpaid Principal Balance	2,379		2,195
Impaired Financing Receivable, Recorded Investment	2,099		1,923
Impaired Financing Receivable, Average Recorded Investment	1,971	$ 1,048
Impaired Financing Receivable, Interest Income, Accrual Method	12	99
Impaired Financing Receivable, Interest Income, Cash Basis Method	12	99
Commercial Real Estate Portfolio Segment [Member] | Other Commercial Real Estate Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	913		922
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	825		836
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	826	362
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	86
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	86
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	205		209
Impaired Financing Receivable, with Related Allowance, Recorded Investment	206		209
Impaired Financing Receivable, Related Allowance	5		6
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	206	220
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	3	3
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	3	3
Residential Portfolio Segment [Member] | Residential Real Estate Owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	830		604
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	689		463
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	539	39
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	6	7
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	6	7
Residential Portfolio Segment [Member] | Residential Real Estate Non-owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	279		284
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	225		236
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	229	257
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	152
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	154
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	171
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	3
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance			176
Impaired Financing Receivable, with Related Allowance, Recorded Investment			179
Impaired Financing Receivable, Related Allowance			$ 28
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		170
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method		$ 3