Note 4 - Loans and the Allowance for Credit Losses - Allocation of the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Loans, Balance			$ 19,959
Charge-offs			(881)		$ (1,095)
Loans, Balance	$ 19,742		19,742		19,959
Charge-offs			(881)		(1,095)
Loans, Net of Unfunded Commitments [Member]
Loans, Balance	19,740	$ 14,209	19,959	$ 13,196	13,196
Charge-offs	(218)	(224)	(881)	(730)
Recoveries	70	141	314	511
Provision for (recovery of) credit losses	150	5,123	350	6,272
Loans, Balance	19,742	19,564	19,742	19,564	19,959
Charge-offs	(218)	(224)	(881)	(730)
Initial allowance on acquired PCD loans		315		315
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, Balance	3,117	1,397	3,246	1,265	1,265
Charge-offs	(108)	(25)	(310)	(190)	(355)
Recoveries	15	11	67	22
Provision for (recovery of) credit losses	(6)	1,035	15	1,321
Loans, Balance	3,018	2,476	3,018	2,476	3,246
Charge-offs	(108)	(25)	(310)	(190)	(355)
Initial allowance on acquired PCD loans		58		58
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans, Balance	4,525	2,657	3,973	1,802	1,802
Charge-offs	0	0	(6)	(11)	(11)
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	337	568	895	1,434
Loans, Balance	4,862	3,256	4,862	3,256	3,973
Charge-offs	0	0	(6)	(11)	(11)
Initial allowance on acquired PCD loans		31		31
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, Balance	10,401	7,742	10,605	7,459	7,459
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	(94)	3,111	(298)	3,394
Loans, Balance	10,307	11,079	10,307	11,079	10,605
Charge-offs	0	0	0	0	0
Initial allowance on acquired PCD loans		226		226
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans, Balance	360	694	514	815	815
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	(68)	32	(222)	(89)
Loans, Balance	292	726	292	726	514
Charge-offs	0	0	0	0	0
Initial allowance on acquired PCD loans		0		0
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, Balance	216	110	258	102	102
Charge-offs	0	0	0	0	0
Recoveries	0	47	0	49
Provision for (recovery of) credit losses	(3)	108	(45)	114
Loans, Balance	213	265	213	265	258
Charge-offs	0	0	0	0	0
Initial allowance on acquired PCD loans		0
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Loans, Balance	475	562	502	460	460
Charge-offs	0	(19)	(75)	(19)	(66)
Recoveries	0	0	0	0
Provision for (recovery of) credit losses	(6)	57	42	159
Loans, Balance	469	600	469	600	502
Charge-offs	0	(19)	(75)	(19)	(66)
Initial allowance on acquired PCD loans		0		0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Loans, Balance	434	955	591	1,215	1,215
Charge-offs	(100)	(157)	(453)	(408)	(528)
Recoveries	50	80	227	430
Provision for (recovery of) credit losses	(12)	(39)	7	(398)
Loans, Balance	372	839	372	839	591
Charge-offs	(100)	(157)	(453)	(408)	(528)
Initial allowance on acquired PCD loans		0		0
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans, Balance	212	92	270	78	78
Charge-offs	(10)	(23)	(37)	(102)	(135)
Recoveries	5	3	20	10
Provision for (recovery of) credit losses	2	251	(44)	337
Loans, Balance	209	323	209	323	270
Charge-offs	$ (10)	(23)	$ (37)	(102)	$ (135)
Initial allowance on acquired PCD loans		$ 0		$ 0

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

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