Note 5 - Credit Quality - Loans Modified as Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Financial Asset, Not Past Due [Member]
Loans modified	$ 1,927	$ 1,792
Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	250	254
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Non-farm, Non-residential [Member] \| Financial Asset, Not Past Due [Member]
Loans modified	662	662
Non-farm, Non-residential [Member] \| Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	0	0
Non-farm, Non-residential [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Single Family Owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Loans modified	1,012	864
Single Family Owner Occupied [Member] \| Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	250	254
Single Family Owner Occupied [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Single Family Non-owner Occupied [Member] \| Financial Asset, Not Past Due [Member]
Loans modified	87	89
Single Family Non-owner Occupied [Member] \| Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	0	0
Single Family Non-owner Occupied [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Commercial and Industrial [Member] \| Financial Asset, Not Past Due [Member]
Loans modified	161	171
Commercial and Industrial [Member] \| Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	0	0
Commercial and Industrial [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Consumer Loans [Member] \| Financial Asset, Not Past Due [Member]
Loans modified	5	6
Consumer Loans [Member] \| Financial Asset, 30 to 89 Days Past Due [Member]
Loans modified	0	0
Consumer Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans modified	0	0
Payment Deferral [Member]
Amortized cost basis	1,450	1,470
Payment Deferral [Member] \| Non-farm, Non-residential [Member]
Amortized cost basis	$ 662	$ 662
Percentage of total financing receivable	0.08%	0.07%
Payment Deferral [Member] \| Single Family Owner Occupied [Member]
Amortized cost basis	$ 540	$ 548
Percentage of total financing receivable	0.08%	0.08%
Payment Deferral [Member] \| Single Family Non-owner Occupied [Member]
Amortized cost basis	$ 87	$ 89
Percentage of total financing receivable	0.04%	0.04%
Payment Deferral [Member] \| Commercial and Industrial [Member]
Amortized cost basis	$ 161	$ 171
Percentage of total financing receivable	0.08%	0.08%
Extended Maturity [Member]
Amortized cost basis	$ 5	$ 6
Extended Maturity [Member] \| Consumer Loans [Member]
Amortized cost basis	$ 5	$ 6
Percentage of total financing receivable	0.01%	0.01%
Extended Maturity [Member] \| Consumer Loans [Member] \| Minimum [Member]
Extended term (Month)		60 months
Extended Maturity [Member] \| Consumer Loans [Member] \| Maximum [Member]
Extended term (Month)		84 months
Principal Forgiveness [Member]
Amortized cost basis	$ 3	$ 5
Principal Forgiveness [Member] \| Single Family Owner Occupied [Member]
Amortized cost basis	$ 3	$ 5
Percentage of total financing receivable	0.00%	0.00%
Term Extension and Rate Reduction [Member]
Amortized cost basis	$ 719	$ 565
Term Extension and Rate Reduction [Member] \| Single Family Owner Occupied [Member]
Amortized cost basis	$ 719	$ 565
Percentage of total financing receivable	0.11%	0.08%

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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