Note 3 - Investment Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Debt securities, amortized cost	$ 78,909
Debt securities, fair value	78,132	$ 81,068
US Government Agencies Debt Securities [Member]
Due within one year, amortized cost	20,094
Due within one year, fair value	20,003
Due after one year through five years, amortized cost	36,962
Due after one year through five years, fair value	37,022
Due after five years through ten years, amortized cost
Due after five years through ten years, fair value
Due after ten years, amortized cost
Due after ten years, fair value
Total U.S. Government agency securities, amortized cost	57,056
Total U.S. Government agency securities, fair value	57,025
Debt securities, amortized cost	57,056	57,129
Debt securities, fair value	57,025	56,887
Collateralized Mortgage Backed Securities [Member]
Agency mortgage-backed securities, amortized cost	21,853
Agency mortgage-backed securities, fair value	21,107
Debt securities, amortized cost	21,853	25,276
Debt securities, fair value	$ 21,107	$ 24,181

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