Note 3 - Securities - Amortized Cost and Fair Values of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jun. 30, 2019
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	$ 5,543
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	5,576
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	15,986
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	16,319
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	18,947
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	19,273
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	27,123
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	28,409
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis	67,599
Available-for-sale Securities, Debt Maturities, Single Maturity Date	69,577
Total available-for-sale securities, Amortized Cost Basis	130,420	$ 142,028
Total available-for-sale securities	133,082	144,010
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount	412
Held-to-maturity Securities, Debt Maturities, Year Five Through Ten Years, Fair Value	434
Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount	3,168
Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value	3,425
Held-to-maturity Securities	3,580	3,786
Total held-to-maturity securities, Fair Value	3,859	$ 3,821
U.S. Government-sponsored Mortgage-backed and Related Securities [Member]
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Amortized Cost Basis	62,821
Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value	$ 63,505