Note 4 - Loans Receivable - Delinquencies Within the Loan Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Loans receivable	$ 1,421,483	$ 1,355,423
Non-accrual Loans	6,957	3,298
Nonaccrual, with ACL	2,604
Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	2,078	5,614
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	369	1,076
Financial Asset, Past Due [Member]
Loans receivable	2,447	6,690
Financial Asset, Not Past Due [Member]
Loans receivable	1,409,475	1,345,435
Residential Portfolio Segment [Member]
Loans receivable	182,953	195,703	$ 186,229
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member]
Loans receivable	133,437	135,947
Non-accrual Loans	322	483
Nonaccrual, with ACL	0
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	687	1,798
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	329	330
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member] | Financial Asset, Past Due [Member]
Loans receivable	1,016	2,128
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	132,099	133,336
Residential Portfolio Segment [Member] | One-to-Four Family Construction [Member]
Loans receivable	49,516	59,756
Non-accrual Loans	0	0
Nonaccrual, with ACL	0
Residential Portfolio Segment [Member] | One-to-Four Family Construction [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	0	500
Residential Portfolio Segment [Member] | One-to-Four Family Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Residential Portfolio Segment [Member] | One-to-Four Family Construction [Member] | Financial Asset, Past Due [Member]
Loans receivable	0	500
Residential Portfolio Segment [Member] | One-to-Four Family Construction [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	49,516	59,256
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	875,545	826,549	743,326
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Loans receivable	577,736	539,070
Non-accrual Loans	668	350
Nonaccrual, with ACL	0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	0	780
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Past Due [Member]
Loans receivable	0	780
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	577,068	537,940
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans receivable	158,519	151,145
Non-accrual Loans	0	0
Nonaccrual, with ACL	0
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Financial Asset, Past Due [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	158,519	151,145
Commercial Real Estate Portfolio Segment [Member] | Farmland Loan [Member]
Loans receivable	139,290	136,334
Non-accrual Loans	2,313	754
Nonaccrual, with ACL	1,734
Commercial Real Estate Portfolio Segment [Member] | Farmland Loan [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	233	1,620
Commercial Real Estate Portfolio Segment [Member] | Farmland Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Farmland Loan [Member] | Financial Asset, Past Due [Member]
Loans receivable	233	1,620
Commercial Real Estate Portfolio Segment [Member] | Farmland Loan [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	135,010	133,960
Home Equity Portfolio Segment [Member]
Loans receivable	80,333	74,271	62,445
Non-accrual Loans	178	107
Nonaccrual, with ACL	0
Home Equity Portfolio Segment [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	425	226
Home Equity Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Home Equity Portfolio Segment [Member] | Financial Asset, Past Due [Member]
Loans receivable	425	226
Home Equity Portfolio Segment [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	79,730	73,938
Consumer Portfolio Segment [Member]
Loans receivable	30,065	27,609	25,775
Non-accrual Loans	67	25
Nonaccrual, with ACL	21
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	73	93
Consumer Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Consumer Portfolio Segment [Member] | Financial Asset, Past Due [Member]
Loans receivable	73	93
Consumer Portfolio Segment [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	29,904	27,491
Commercial Portfolio Segment [Member]
Loans receivable	252,587	231,291	$ 234,741
Commercial Portfolio Segment [Member] | Commercial Loans [Member]
Loans receivable	129,084	127,255
Non-accrual Loans	213	44
Nonaccrual, with ACL	0
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	633	597
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	40	746
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Financial Asset, Past Due [Member]
Loans receivable	673	1,343
Commercial Portfolio Segment [Member] | Commercial Loans [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	128,198	125,868
Commercial Portfolio Segment [Member] | Agricultural Loan [Member]
Loans receivable	123,503	104,036
Non-accrual Loans	3,196	1,535
Nonaccrual, with ACL	849
Commercial Portfolio Segment [Member] | Agricultural Loan [Member] | Financing Receivables, 30 to 89 Days Past Due [Member]
Loans receivable	27	0
Commercial Portfolio Segment [Member] | Agricultural Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	0	0
Commercial Portfolio Segment [Member] | Agricultural Loan [Member] | Financial Asset, Past Due [Member]
Loans receivable	27	0
Commercial Portfolio Segment [Member] | Agricultural Loan [Member] | Financial Asset, Not Past Due [Member]
Loans receivable	$ 119,431	$ 102,501