Note 3 - Securities - Amortized Cost and Fair Value of Securities Available-for-sale and Securities Held-to-maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020
Available-for-sale securities, amortized cost	$ 131,440	$ 138,525
Available-for-sale securities, gross unrealized gains	5,499	5,411
Available-for-sale securities, gross unrealized losses	(36)	(18)
Available-for-sale securities, fair value	136,903	143,918
Held-to-maturity, amortized cost	3,441	3,541
Held-to-maturity, gross unrecognized gains	293	327
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,734	3,868
US Treasury Securities [Member]
Available-for-sale securities, amortized cost	749	1,248
Available-for-sale securities, gross unrealized gains	4	8
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value	753	1,256
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	60,795	60,343
Available-for-sale securities, gross unrealized gains	3,238	3,149
Available-for-sale securities, gross unrealized losses	(12)
Available-for-sale securities, fair value	64,021	63,492
Held-to-maturity, amortized cost	3,441	3,541
Held-to-maturity, gross unrecognized gains	293	327
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,734	3,868
US Government-sponsored Enterprises Debt Securities [Member]
Available-for-sale securities, amortized cost	9,880	10,133
Available-for-sale securities, gross unrealized gains	372	399
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value	10,252	10,532
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	44,540	48,645
Available-for-sale securities, gross unrealized gains	1,588	1,515
Available-for-sale securities, gross unrealized losses	(10)	(4)
Available-for-sale securities, fair value	46,118	50,156
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	7,913	8,444
Available-for-sale securities, gross unrealized gains	72	55
Available-for-sale securities, gross unrealized losses	(4)	(2)
Available-for-sale securities, fair value	7,981	8,497
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	7,563	9,712
Available-for-sale securities, gross unrealized gains	225	285
Available-for-sale securities, gross unrealized losses	(10)	(12)
Available-for-sale securities, fair value	$ 7,778	$ 9,985

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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