Note 3 - Securities - Amortized Cost and Fair Value of Securities Available-for-sale and Securities Held-to-maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Available-for-sale securities, amortized cost	$ 138,525	$ 142,028
Available-for-sale securities, gross unrealized gains	5,411	2,492
Available-for-sale securities, gross unrealized losses	(18)	(510)
Available-for-sale securities, fair value	143,918	144,010
Held-to-maturity, amortized cost	3,541	3,786
Held-to-maturity, gross unrecognized gains	327	35
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,868	3,821
US Treasury Securities [Member]
Available-for-sale securities, amortized cost	1,248
Available-for-sale securities, gross unrealized gains	8
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value	1,256
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	60,343	56,405
Available-for-sale securities, gross unrealized gains	3,149	1,557
Available-for-sale securities, gross unrealized losses		(33)
Available-for-sale securities, fair value	63,492	57,929
Held-to-maturity, amortized cost	3,541	3,786
Held-to-maturity, gross unrecognized gains	327	35
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,868	3,821
US Government-sponsored Enterprises Debt Securities [Member]
Available-for-sale securities, amortized cost	10,133	19,227
Available-for-sale securities, gross unrealized gains	399	287
Available-for-sale securities, gross unrealized losses		(1)
Available-for-sale securities, fair value	10,532	19,513
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	48,645	56,309
Available-for-sale securities, gross unrealized gains	1,515	450
Available-for-sale securities, gross unrealized losses	(4)	(448)
Available-for-sale securities, fair value	50,156	56,311
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	9,712	10,087
Available-for-sale securities, gross unrealized gains	285	198
Available-for-sale securities, gross unrealized losses	(12)	(28)
Available-for-sale securities, fair value	9,985	$ 10,257
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	8,444
Available-for-sale securities, gross unrealized gains	55
Available-for-sale securities, gross unrealized losses	(2)
Available-for-sale securities, fair value	$ 8,497

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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