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Note 4 - Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Jun. 30, 2020
Beginning balance	$ 5,767	$ 3,909	$ 5,678	$ 3,788
Provision for loan losses	130	185	260	315
Loans charged-off	(12)	(7)	(78)	(23)
Recoveries	27	8	52	15
Total ending allowance balance	5,912	4,095	5,912	4,095
Individually evaluated for impairment					$ 9	$ 34
Total ending allowance balance	5,767	4,095	5,678	3,788	5,912	5,678
Loans individually evaluated for impairment					2,343	1,923
Total ending loans balance					558,864	544,797
Financial Asset Acquired [Member]
Collectively evaluated for impairment					185	197
Loans collectively evaluated for impairment					40,640	48,969
Financial Asset Originated [Member]
Collectively evaluated for impairment					5,718	5,447
Loans collectively evaluated for impairment					515,881	493,905
Commercial Portfolio Segment [Member]
Beginning balance	940	649	947	660
Provision for loan losses	(82)	117	(67)	106
Loans charged-off			(22)
Recoveries
Total ending allowance balance	858	766	858	766
Individually evaluated for impairment					3	28
Total ending allowance balance	858	766	947	660	858	947
Loans individually evaluated for impairment					148	179
Total ending loans balance					159,140	157,328
Commercial Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					661	1,095
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					855	919
Loans collectively evaluated for impairment					158,331	156,054
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	3,694	2,645	3,623	2,575
Provision for loan losses	122	6	192	75
Loans charged-off
Recoveries	1	1	2	2
Total ending allowance balance	3,817	2,652	3,817	2,652
Individually evaluated for impairment						6
Total ending allowance balance	3,817	2,652	3,623	2,575	3,817	3,623
Loans individually evaluated for impairment					1,151	1,045
Total ending loans balance					254,464	245,957
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					101	103
Loans collectively evaluated for impairment					7,824	8,072
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					3,716	3,514
Loans collectively evaluated for impairment					245,489	236,840
Residential Portfolio Segment [Member]
Beginning balance	997	550	989	494
Provision for loan losses	31	64	39	120
Loans charged-off
Recoveries		1		1
Total ending allowance balance	1,028	615	1,028	615
Individually evaluated for impairment					6
Total ending allowance balance	1,028	615	989	494	1,028	989
Loans individually evaluated for impairment					1,044	699
Total ending loans balance					120,997	120,119
Residential Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					84	94
Loans collectively evaluated for impairment					23,220	27,252
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					938	895
Loans collectively evaluated for impairment					96,733	92,168
Consumer Portfolio Segment [Member]
Beginning balance	136	65	119	59
Provision for loan losses	59	(2)	96	14
Loans charged-off	(12)	(7)	(56)	(23)
Recoveries	26	6	50	12
Total ending allowance balance	209	62	209	62
Individually evaluated for impairment
Total ending allowance balance	$ 209	$ 62	$ 119	$ 59	209	119
Loans individually evaluated for impairment
Total ending loans balance					24,263	21,393
Consumer Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					8,935	12,550
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					209	119
Loans collectively evaluated for impairment					$ 15,328	$ 8,843