Note 2 - Securities - Amortized Cost and Fair Value of Securities Available-for-sale and Securities Held-to-maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Available-for-sale securities, amortized cost	$ 145,568	$ 146,097
Available-for-sale securities, gross unrealized gains	604	909
Available-for-sale securities, gross unrealized losses	(2,339)	(2,978)
Available-for-sale securities, fair value	143,833	144,028
Held-to-maturity, amortized cost	3,824	4,024
Held-to-maturity, gross unrecognized gains	28	24
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,852	4,048
US Government-sponsored Enterprises Debt Securities [Member]
Available-for-sale securities, amortized cost	18,431	16,488
Available-for-sale securities, gross unrealized gains	58	6
Available-for-sale securities, gross unrealized losses	(241)	(372)
Available-for-sale securities, fair value	18,248	16,122
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	57,619	56,964
Available-for-sale securities, gross unrealized gains	427	339
Available-for-sale securities, gross unrealized losses	(544)	(713)
Available-for-sale securities, fair value	57,502	56,590
Held-to-maturity, amortized cost	3,824	4,024
Held-to-maturity, gross unrecognized gains	28	24
Held-to-maturity, gross unrecognized losses
Held-to-maturity, fair value	3,852	4,048
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	61,239	65,062
Available-for-sale securities, gross unrealized gains	75	6
Available-for-sale securities, gross unrealized losses	(1,392)	(1,660)
Available-for-sale securities, fair value	59,922	63,408
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	1,418	1,432
Available-for-sale securities, gross unrealized gains
Available-for-sale securities, gross unrealized losses	(12)	(17)
Available-for-sale securities, fair value	1,406	1,415
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	6,861	5,973
Available-for-sale securities, gross unrealized gains	44	9
Available-for-sale securities, gross unrealized losses	(150)	(216)
Available-for-sale securities, fair value	$ 6,755	5,766
Pooled Trust Preferred Securities Subject to Mandatory Redemption [Member]
Available-for-sale securities, amortized cost		178
Available-for-sale securities, gross unrealized gains		549
Available-for-sale securities, gross unrealized losses
Available-for-sale securities, fair value		$ 727

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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