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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, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Jun. 30, 2019
Beginning balance	$ 4,095	$ 3,569	$ 3,788	$ 3,422
Provision for loan losses	445	105	760	(555)
Loans charged-off	(91)	(34)	(114)	(110)
Recoveries	19	16	34	899
Total ending allowance balance	4,468	3,656	4,468	3,656
Individually evaluated for impairment					$ 9	$ 9
Collectively evaluated for impairment						3,779
Total ending allowance balance	4,095	3,656	3,788	3,422	4,468	3,788
Loans individually evaluated for impairment					1,524	1,189
Loans collectively evaluated for impairment						368,877
Total ending loans balance					468,849	370,066
Financial Asset Acquired [Member]
Collectively evaluated for impairment					50
Loans collectively evaluated for impairment					52,070
Financial Asset Originated [Member]
Collectively evaluated for impairment					4,409
Loans collectively evaluated for impairment					415,255
Commercial Portfolio Segment [Member]
Beginning balance	766	622	660	586
Provision for loan losses	25		131	36
Loans charged-off
Recoveries
Total ending allowance balance	791	622	791	622
Individually evaluated for impairment					1	2
Collectively evaluated for impairment						658
Total ending allowance balance	791	622	660	586	791	660
Loans individually evaluated for impairment					177	174
Loans collectively evaluated for impairment						80,413
Total ending loans balance					85,979	80,587
Commercial Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					1,527
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					790
Loans collectively evaluated for impairment					84,275
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	2,652	2,397	2,575	2,277
Provision for loan losses	203	102	278	(591)
Loans charged-off		(25)		(80)
Recoveries	1	7	3	875
Total ending allowance balance	2,856	2,481	2,856	2,481
Individually evaluated for impairment					8	7
Collectively evaluated for impairment						2,568
Total ending allowance balance	2,856	2,481	2,575	2,277	2,856	2,575
Loans individually evaluated for impairment					1,063	658
Loans collectively evaluated for impairment						210,709
Total ending loans balance					246,038	211,367
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					13
Loans collectively evaluated for impairment					9,462
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					2,835
Loans collectively evaluated for impairment					235,513
Residential Portfolio Segment [Member]
Beginning balance	615	496	494	499
Provision for loan losses	116	5	236	(2)
Loans charged-off
Recoveries	1	2	2	6
Total ending allowance balance	732	503	732	503
Individually evaluated for impairment
Collectively evaluated for impairment						494
Total ending allowance balance	732	503	494	499	732	494
Loans individually evaluated for impairment					284	357
Loans collectively evaluated for impairment						72,591
Total ending loans balance					115,209	72,948
Residential Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment					37
Loans collectively evaluated for impairment					27,562
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					695
Loans collectively evaluated for impairment					87,363
Consumer Portfolio Segment [Member]
Beginning balance	62	54	59	60
Provision for loan losses	101	(2)	115	2
Loans charged-off	(91)	(9)	(114)	(30)
Recoveries	17	7	29	18
Total ending allowance balance	89	50	89	50
Individually evaluated for impairment
Collectively evaluated for impairment						59
Total ending allowance balance	$ 89	$ 50	$ 59	$ 60	89	59
Loans individually evaluated for impairment
Loans collectively evaluated for impairment						5,164
Total ending loans balance					21,623	$ 5,164
Consumer Portfolio Segment [Member] \| Financial Asset Acquired [Member]
Collectively evaluated for impairment
Loans collectively evaluated for impairment					13,519
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Collectively evaluated for impairment					89
Loans collectively evaluated for impairment					$ 8,104