Note 3 - Loans Receivable - Nonaccrual Loans by Class (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Total nonaccrual loans	$ 3,098	$ 1,796
Real Estate Portfolio Segment [Member] | One-to-four Family Loan [Member]
Total nonaccrual loans	1,939	698
Real Estate Portfolio Segment [Member] | Multi-family Loan [Member]
Total nonaccrual loans	287	0
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member]
Total nonaccrual loans	166	109
Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Total nonaccrual loans	25	29
Consumer Portfolio Segment [Member] | Home Equity Loan [Member]
Total nonaccrual loans	74	112
Consumer Portfolio Segment [Member] | Automobile and Other Loan [Member]
Total nonaccrual loans	607	848
Commercial Portfolio Segment [Member]
Total nonaccrual loans	$ 0	$ 0