Note 4 - Loans and the Allowance for Credit Losses - Allocation of the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Loans, Balance			$ 19,959
Charge-offs			(663)		$ (1,095)
Charge-offs			(663)		(1,095)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 19,740		19,740		19,959
Loans, Net of Unfunded Commitments [Member]
Loans, Balance	19,321	$ 13,319	19,959	$ 13,196	13,196
Charge-offs	(321)	(194)	(663)	(506)
Recoveries	140	184	244	369
Provision for (recovery of) credit losses	600	900	200	1,150
Charge-offs	(321)	(194)	(663)	(506)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	19,740	14,209	19,740	14,209	19,959
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, Balance	3,154	1,286	3,246	1,265	1,265
Charge-offs	(102)	0	(202)	(165)	(355)
Recoveries	39	6	52	10
Provision for (recovery of) credit losses	26	105	21	287
Charge-offs	(102)	0	(202)	(165)	(355)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	3,117	1,397	3,117	1,397	3,246
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans, Balance	4,068	1,765	3,973	1,802	1,802
Charge-offs	0	(11)	(6)	(11)	(11)
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	457	903	558	866
Charge-offs	0	(11)	(6)	(11)	(11)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	4,525	2,657	4,525	2,657	3,973
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, Balance	10,298	7,635	10,605	7,459	7,459
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	103	107	(204)	283
Charge-offs	0	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	10,401	7,742	10,401	7,742	10,605
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans, Balance	358	792	514	815	815
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	2	(98)	(154)	(121)
Charge-offs	0	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	360	694	360	694	514
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, Balance	237	111	258	102	102
Charge-offs	0	0	0	0	0
Recoveries	0	1	0	2
Provision for (recovery of) credit losses	(21)	(2)	(42)	6
Charge-offs	0	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	216	110	216	110	258
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Loans, Balance	489	553	502	460	460
Charge-offs	(75)	0	(75)	0	(66)
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	61	9	48	102
Charge-offs	(75)	0	(75)	0	(66)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	475	562	475	562	502
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Loans, Balance	491	1,083	591	1,215	1,215
Charge-offs	(124)	(131)	(353)	(251)	(528)
Recoveries	97	172	177	349
Provision for (recovery of) credit losses	(30)	(169)	19	(358)
Charge-offs	(124)	(131)	(353)	(251)	(528)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	434	955	434	955	591
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans, Balance	226	94	270	78	78
Charge-offs	(20)	(52)	(27)	(79)	(135)
Recoveries	4	5	15	8
Provision for (recovery of) credit losses	2	45	(46)	85
Charge-offs	(20)	(52)	(27)	(79)	(135)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 212	$ 92	$ 212	$ 92	$ 270

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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