Note 4 - Loans and the Allowance for Loan Losses - Outstanding Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Loans	$ 747,885		$ 619,718
Deferred loan (fees) costs, net	(635)		3,561
Allowance for loan losses	(9,600)	$ (8,835)	(7,243)	$ (7,226)	$ (7,058)	$ (6,958)
Total net loans	737,650		616,036
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	167,770		47,892
Allowance for loan losses	(957)	(788)	(617)	(763)	(721)	(914)
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans	74,209		78,785
Allowance for loan losses	(746)	(691)	(653)	(661)	(627)	(538)
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans	333,768		316,986
Allowance for loan losses	(4,777)	(4,405)	(3,426)	(3,087)	(2,997)	(2,686)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans	27,886		31,181
Allowance for loan losses	(568)	(476)	(481)	(640)	(597)	(758)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans	12,848		14,530
Allowance for loan losses	(174)	(173)	(163)	(174)	(177)	(214)
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Loans	34,894		35,471
Allowance for loan losses	(490)	(474)	(393)	(433)	(468)	(464)
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Loans	92,248		90,310
Allowance for loan losses	(1,779)	(1,712)	(1,409)	(1,366)	(1,372)	(1,289)
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans	4,262		4,563
Allowance for loan losses	$ (109)	$ (116)	$ (101)	$ (102)	$ (99)	$ (95)

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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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