Note 4 - Loans and Allowance for Credit Losses - Aging of Recorded Investment in Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable	$ 629,607	$ 622,414
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	3,962	3,798
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	622	456
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	750	536
Financial Asset, Past Due [Member]
Financing Receivable	5,334	4,790
Financial Asset, Not Past Due [Member]
Financing Receivable	624,273	617,624
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member]
Financing Receivable	133,523	133,601
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	2,024	2,104
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	467	335
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	696	482
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Financial Asset, Past Due [Member]
Financing Receivable	3,187	2,921
Residential Portfolio Segment [Member] | One-to-four Family Loan [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	130,336	130,680
Residential Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Financing Receivable	60,992	63,301
Residential Portfolio Segment [Member] | Multifamily [Member]
Financing Receivable	43,600	39,946
Residential Portfolio Segment [Member] | Multifamily [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Financial Asset, Past Due [Member]
Financing Receivable	0	0
Residential Portfolio Segment [Member] | Multifamily [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	43,600	39,946
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Financing Receivable	60,992	63,301
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	321	396
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	24	70
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset, Past Due [Member]
Financing Receivable	345	466
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	60,647	62,835
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Financing Receivable	55,020	56,373
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	186	302
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	45	51
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset, Past Due [Member]
Financing Receivable	231	353
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	54,789	56,020
Construction [Member] | One-to-four Family Residential Construction [Member]
Financing Receivable	15,920	15,667
Construction [Member] | One-to-four Family Residential Construction [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	0	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	86	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Financial Asset, Past Due [Member]
Financing Receivable	86	0
Construction [Member] | One-to-four Family Residential Construction [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	15,834	15,667
Construction [Member] | Other Construction, Development and Land [Member]
Financing Receivable	78,079	76,669
Construction [Member] | Other Construction, Development and Land [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	140	162
Construction [Member] | Other Construction, Development and Land [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	0	0
Construction [Member] | Other Construction, Development and Land [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	54	54
Construction [Member] | Other Construction, Development and Land [Member] | Financial Asset, Past Due [Member]
Financing Receivable	194	216
Construction [Member] | Other Construction, Development and Land [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	77,885	76,453
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Financing Receivable	174,817	168,645
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	1,145	834
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	0	0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Past Due [Member]
Financing Receivable	1,145	834
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	173,672	167,811
Commercial Portfolio Segment [Member] | Commercial Business [Member]
Financing Receivable	67,656	68,212
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable	146	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable	0	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable	0	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Financial Asset, Past Due [Member]
Financing Receivable	146	0
Commercial Portfolio Segment [Member] | Commercial Business [Member] | Financial Asset, Not Past Due [Member]
Financing Receivable	$ 67,510	$ 68,212