Note 4 - Loans and the Allowance for Loan Losses - Allocation of the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Beginning balance	$ 10,402	$ 9,962	$ 10,352	$ 9,902	$ 9,902
Charge-offs	(96)	(152)	(469)	(544)	(938)
Recoveries	213	68	336	145	263
Provision	400	250	700	625	1,125
Ending balance	10,919	10,128	10,919	10,128	10,352
Recoveries	213	68	336	145	263
Provision	400	250	700	625	1,125
Allowance for loan losses, individually evaluated for impairment	39		39		28
Allowance for loan losses, collectively evaluated for impairment	10,880		10,880		10,324
Loans, individually evaluated for impairment	1,394		1,394		4,857
Loans, collectively evaluated for impairment	860,758		860,758		833,730
Ending balance	862,152	10,128	862,152	10,128	838,587
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Beginning balance	893	777	1,074	950	950
Charge-offs	0	(8)	0	(161)
Recoveries	11	5	17	47
Provision	(2)	109	(189)	47
Ending balance	902	883	902	883	1,074
Recoveries	11	5	17	47
Provision	(2)	109	(189)	47
Allowance for loan losses, individually evaluated for impairment	16		16		0
Allowance for loan losses, collectively evaluated for impairment	886		886		1,074
Loans, individually evaluated for impairment	19		19		0
Loans, collectively evaluated for impairment	84,359		84,359		99,804
Ending balance	84,378	883	84,378	883	99,804
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Beginning balance	947	698	791	757	757
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	147	(17)	303	(76)
Ending balance	1,094	681	1,094	681	791
Recoveries	0	0	0	0
Provision	147	(17)	303	(76)
Allowance for loan losses, individually evaluated for impairment	0		0		0
Allowance for loan losses, collectively evaluated for impairment	1,094		1,094		791
Loans, individually evaluated for impairment	235		235		238
Loans, collectively evaluated for impairment	125,572		125,572		126,218
Ending balance	125,807	681	125,807	681	126,456
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Beginning balance	4,322	5,132	4,549	5,089	5,089
Charge-offs	0	0	(19)	0
Recoveries	1	1	0	4
Provision	72	212	(135)	252
Ending balance	4,395	5,345	4,395	5,345	4,549
Recoveries	1	1	0	4
Provision	72	212	(135)	252
Allowance for loan losses, individually evaluated for impairment	0		0		0
Allowance for loan losses, collectively evaluated for impairment	4,395		4,395		4,549
Loans, individually evaluated for impairment	97		97		3,697
Loans, collectively evaluated for impairment	447,883		447,883		414,912
Ending balance	447,980	5,345	447,980	5,345	418,609
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Beginning balance	1,545	657	1,325	554	554
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	214	(51)	434	52
Ending balance	1,759	606	1,759	606	1,325
Recoveries	0	0	0	0
Provision	214	(51)	434	52
Allowance for loan losses, individually evaluated for impairment	0		0		5
Allowance for loan losses, collectively evaluated for impairment	1,759		1,759		1,320
Loans, individually evaluated for impairment	98		98		102
Loans, collectively evaluated for impairment	60,793		60,793		51,424
Ending balance	60,891	606	60,891	606	51,526
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Beginning balance	132	169	168	164	164
Charge-offs	0	0	0	0
Recoveries	1	0	2	1
Provision	6	(38)	(31)	(34)
Ending balance	139	131	139	131	168
Recoveries	1	0	2	1
Provision	6	(38)	(31)	(34)
Allowance for loan losses, individually evaluated for impairment	23		23		23
Allowance for loan losses, collectively evaluated for impairment	116		116		145
Loans, individually evaluated for impairment	691		691		557
Loans, collectively evaluated for impairment	15,176		15,176		15,280
Ending balance	15,867	131	15,867	131	15,837
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Beginning balance	554	484	426	499	499
Charge-offs	0	0	0	0
Recoveries	0	1	0	2
Provision	39	(31)	167	(47)
Ending balance	593	454	593	454	426
Recoveries	0	1	0	2
Provision	39	(31)	167	(47)
Allowance for loan losses, individually evaluated for impairment	0		0		0
Allowance for loan losses, collectively evaluated for impairment	593		593		426
Loans, individually evaluated for impairment	254		254		263
Loans, collectively evaluated for impairment	34,491		34,491		32,530
Ending balance	34,745	454	34,745	454	32,793
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Beginning balance	1,880	1,928	1,911	1,768	1,768
Charge-offs	(85)	(128)	(419)	(346)
Recoveries	197	58	311	77
Provision	(92)	52	97	411
Ending balance	1,900	1,910	1,900	1,910	1,911
Recoveries	197	58	311	77
Provision	(92)	52	97	411
Allowance for loan losses, individually evaluated for impairment	0		0		0
Allowance for loan losses, collectively evaluated for impairment	1,900		1,900		1,911
Loans, individually evaluated for impairment	0		0		0
Loans, collectively evaluated for impairment	87,907		87,907		89,046
Ending balance	87,907	1,910	87,907	1,910	89,046
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Beginning balance	129	117	108	121	121
Charge-offs	(11)	(16)	(31)	(37)
Recoveries	3	3	6	14
Provision	16	14	54	20
Ending balance	137	118	137	118	108
Recoveries	3	3	6	14
Provision	16	14	54	20
Allowance for loan losses, individually evaluated for impairment	0		0		0
Allowance for loan losses, collectively evaluated for impairment	137		137		108
Loans, individually evaluated for impairment	0		0		0
Loans, collectively evaluated for impairment	4,577		4,577		4,516
Ending balance	$ 4,577	$ 118	$ 4,577	$ 118	$ 4,516

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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