Note 3 - Securities - Amortized Cost and Fair Value of Securities Available-for-sale and Securities Held-to-maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019
Available-for-sale securities, amortized cost	$ 134,942	$ 142,028
Available-for-sale securities, gross unrealized gains	4,447	2,492
Available-for-sale securities, gross unrealized losses	(6)	(510)
Available-for-sale securities, fair value	139,383	144,010
Held-to-maturity, amortized cost	3,580	3,786
Held-to-maturity, gross unrecognized gains	212	35
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,792	3,821
US Treasury Securities [Member]
Available-for-sale securities, amortized cost	1,747
Available-for-sale securities, gross unrealized gains	14
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value	1,761
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	56,969	56,405
Available-for-sale securities, gross unrealized gains	1,969	1,557
Available-for-sale securities, gross unrealized losses	(5)	(33)
Available-for-sale securities, fair value	58,933	57,929
Held-to-maturity, amortized cost	3,580	3,786
Held-to-maturity, gross unrecognized gains	212	35
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,792	3,821
US Government-sponsored Enterprises Debt Securities [Member]
Available-for-sale securities, amortized cost	10,574	19,227
Available-for-sale securities, gross unrealized gains	290	287
Available-for-sale securities, gross unrealized losses		(1)
Available-for-sale securities, fair value	10,864	19,513
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	55,248	56,309
Available-for-sale securities, gross unrealized gains	1,822	450
Available-for-sale securities, gross unrealized losses	(1)	(448)
Available-for-sale securities, fair value	57,069	56,311
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	9,007	10,087
Available-for-sale securities, gross unrealized gains	346	198
Available-for-sale securities, gross unrealized losses		(28)
Available-for-sale securities, fair value	9,353	$ 10,257
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	1,397
Available-for-sale securities, gross unrealized gains	6
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value	$ 1,403

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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