Note 4 - Loans and Allowance for Credit Losses - Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Real Estate [Member]
Collateral Dependent Loans	$ 4,818	$ 3,395
Equipment [Member]
Collateral Dependent Loans	2,029
Real Estate, Other [Member]
Collateral Dependent Loans	146	38
Collateral Pledged [Member]
Collateral Dependent Loans	6,993	3,433
Allowance for Credit Loss	49	69
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Real Estate [Member]
Collateral Dependent Loans	1,506	1,651
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Equipment [Member]
Collateral Dependent Loans	0
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	1,506	1,651
Allowance for Credit Loss	0	9
Residential Portfolio Segment [Member] | Multifamily [Member] | Real Estate [Member]
Collateral Dependent Loans	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Equipment [Member]
Collateral Dependent Loans	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	0	0
Allowance for Credit Loss	0	0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Real Estate [Member]
Collateral Dependent Loans	540	548
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Equipment [Member]
Collateral Dependent Loans	0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	540	548
Allowance for Credit Loss	0	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Real Estate [Member]
Collateral Dependent Loans	0	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Equipment [Member]
Collateral Dependent Loans	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	0	0
Allowance for Credit Loss	0	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Real Estate [Member]
Collateral Dependent Loans	86	87
Construction [Member] | One-to-four Family Residential Construction [Member] | Equipment [Member]
Collateral Dependent Loans	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	86	87
Allowance for Credit Loss	49	60
Construction [Member] | Other Construction, Development and Land [Member] | Real Estate [Member]
Collateral Dependent Loans	54	54
Construction [Member] | Other Construction, Development and Land [Member] | Equipment [Member]
Collateral Dependent Loans	0
Construction [Member] | Other Construction, Development and Land [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Construction [Member] | Other Construction, Development and Land [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	54	54
Allowance for Credit Loss	0	0
Commercial Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Real Estate [Member]
Collateral Dependent Loans	2,632	1,055
Commercial Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Equipment [Member]
Collateral Dependent Loans	0
Commercial Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	0	0
Commercial Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	2,632	1,055
Allowance for Credit Loss	0	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Real Estate [Member]
Collateral Dependent Loans	0	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Equipment [Member]
Collateral Dependent Loans	2,029
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Real Estate, Other [Member]
Collateral Dependent Loans	146	38
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Collateral Pledged [Member]
Collateral Dependent Loans	2,175	38
Allowance for Credit Loss	$ 0	$ 0