Note 3 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Impaired Financing Receivable, Related Allowance	$ 29		$ 29
Impaired Financing Receivable, Unpaid Principal Balance	2,252		2,059
Impaired Financing Receivable, Recorded Investment	2,081		2,060
Impaired Financing Receivable, Average Recorded Investment	2,062	$ 1,939
Impaired Financing Receivable, Interest Income, Accrual Method	15	12
Impaired Financing Receivable, Interest Income, Cash Basis Method	15	12
Commercial Portfolio Segment [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	87		100
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	87		100
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	71	114
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	1	2
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	1	2
Commercial Real Estate Portfolio Segment [Member] | Other Commercial Real Estate Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,499		1,330
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,376		1,330
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,369	1,053
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	11	10
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	11	10
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	228		231
Impaired Financing Receivable, with Related Allowance, Recorded Investment	230		232
Impaired Financing Receivable, Related Allowance	29		29
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	231	343
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	3
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	3
Residential Portfolio Segment [Member] | Residential Real Estate Owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	129		101
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	99		101
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	99	102
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method
Residential Portfolio Segment [Member] | Residential Real Estate Non-owner Occupied Loans [Member]
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	309		297
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	289		$ 297
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	292	327
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method