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Note 4 - Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Jun. 30, 2020
Beginning balance	$ 5,912	$ 4,095	$ 5,678	$ 3,788
Provision for loan losses	185	445	445	760
Loans charged-off	(43)	(91)	(121)	(114)
Recoveries	22	19	74	34
Total ending allowance balance	6,076	4,468	6,076	4,468
Individually evaluated for impairment					$ 5	$ 34
Total ending allowance balance	5,912	4,468	5,678	3,788	6,076	5,678
Loans individually evaluated for impairment					2,074	1,923
Total ending loans balance					554,426	544,797
Financial Asset Acquired [Member]
Collectively evaluated for impairment					178	197
Loans collectively evaluated for impairment					38,411	48,969
Financial Asset Originated [Member]
Collectively evaluated for impairment					5,893	5,447
Loans collectively evaluated for impairment					513,941	493,905
Commercial Portfolio Segment [Member]
Beginning balance	858	766	947	660
Provision for loan losses	79	25	12	131
Loans charged-off			(22)
Recoveries
Total ending allowance balance	937	791	937	791
Individually evaluated for impairment					1	28
Total ending allowance balance	937	791	947	660	937	947
Loans individually evaluated for impairment					446	179
Total ending loans balance					129,417	157,328
Commercial Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					907	1,095
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					936	919
Loans collectively evaluated for impairment					128,064	156,054
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	3,817	2,652	3,623	2,575
Provision for loan losses	(109)	203	83	278
Loans charged-off
Recoveries	1	1	3	3
Total ending allowance balance	3,709	2,856	3,709	2,856
Individually evaluated for impairment						6
Total ending allowance balance	3,709	2,856	3,623	2,575	3,709	3,623
Loans individually evaluated for impairment					936	1,045
Total ending loans balance					262,375	245,957
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					99	103
Loans collectively evaluated for impairment					7,766	8,072
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					3,610	3,514
Loans collectively evaluated for impairment					253,673	236,840
Residential Portfolio Segment [Member]
Beginning balance	1,028	615	989	494
Provision for loan losses	166	116	205	236
Loans charged-off	(4)		(4)
Recoveries	1	1	1	2
Total ending allowance balance	1,191	732	1,191	732
Individually evaluated for impairment					4
Total ending allowance balance	1,191	732	989	494	1,191	989
Loans individually evaluated for impairment					692	699
Total ending loans balance					136,608	120,119
Residential Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					79	94
Loans collectively evaluated for impairment					22,067	27,252
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					1,108	895
Loans collectively evaluated for impairment					113,849	92,168
Consumer Portfolio Segment [Member]
Beginning balance	209	62	119	59
Provision for loan losses	49	101	145	115
Loans charged-off	(39)	(91)	(95)	(114)
Recoveries	20	17	70	29
Total ending allowance balance	239	89	239	89
Individually evaluated for impairment
Total ending allowance balance	$ 239	$ 89	$ 119	$ 59	239	119
Loans individually evaluated for impairment
Total ending loans balance					26,026	21,393
Consumer Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					7,671	12,550
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					239	119
Loans collectively evaluated for impairment					$ 18,355	$ 8,843