Note 4 - Loans Receivable - COVID Loan Forbearance Program (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Number of loans	30
Principal balance	$ 10,337
Principal Amount Deferred	$ 53
Multi-family Mortgage [Member] | COVID 19 [Member] | Small Investment Property Forbearance Agreement [Member]
Number of loans	8
Principal balance	$ 3,092
Principal Amount Deferred	$ 17
Nonresidential Real Estate [Member] | COVID 19 [Member] | Small Investment Property Forbearance Agreement [Member]
Number of loans	10
Principal balance	$ 3,363
Principal Amount Deferred	$ 22
Nonresidential Real Estate [Member] | COVID 19 [Member] | Standard Forbearance Agreement [Member]
Number of loans	2
Principal balance	$ 2,480
Principal Amount Deferred	$ 6
One-to-Four Family Residential Real Estate [Member] | COVID 19 [Member] | Standard Forbearance Agreement [Member]
Number of loans	10
Principal Amount Deferred	$ 8
One To Four Family Residential Real Estate Loans [Member] | COVID 19 [Member] | Standard Forbearance Agreement [Member]
Principal balance	$ 1,402