Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Note 2 - Summary of Significant Accounting Policies / New Authoritative Guidance - Impact of ASU 2016-13 (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Loans, allowance for credit losses	$ 12,279	$ (11,557)	$ 14,193	$ 13,129	$ 12,416
Deferred income taxes		15,759
Liability for credit losses for unfunded commitments		(2,217)
Retained earnings	66,834	(65,953)	64,873
Previously Reported [Member]
Loans, allowance for credit losses		(14,193)
Deferred income taxes		16,046
Liability for credit losses for unfunded commitments		(948)
Retained earnings		(64,873)
Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		2,636
Deferred income taxes		(287)
Liability for credit losses for unfunded commitments		(1,269)
Retained earnings		(1,080)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, allowance for credit losses	1,164	(1,187)	2,215	2,196	2,081
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(2,215)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		1,028
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans, allowance for credit losses	2,509	(2,579)	4,193	4,424	4,530
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(4,193)
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		1,614
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member]
Loans, allowance for credit losses	1,669	(1,814)	747	538	392
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(747)
Construction, Land Acquisition and Development [Member] \| Real Estate Loan [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		(1,067)
Commercial and Industrial [Member]
Loans, allowance for credit losses	4,928		4,099	3,092	2,670
Commercial and Industrial [Member] \| Real Estate Loan [Member]
Loans, allowance for credit losses		(3,887)
Commercial and Industrial [Member] \| Real Estate Loan [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(4,099)
Commercial and Industrial [Member] \| Real Estate Loan [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		212
Consumer Portfolio Segment [Member]
Loans, allowance for credit losses	1,597	(1,677)	1,307	1,259	1,159
Consumer Portfolio Segment [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(1,307)
Consumer Portfolio Segment [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		(370)
State and Political Subdivisions [Member]
Loans, allowance for credit losses	412	(413)	503	491	455
State and Political Subdivisions [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(503)
State and Political Subdivisions [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		90
Unallocated Financing Receivables [Member]
Loans, allowance for credit losses	$ 0	0	$ 1,129	$ 1,129	$ 1,129
Unallocated Financing Receivables [Member] \| Previously Reported [Member]
Loans, allowance for credit losses		(1,129)
Unallocated Financing Receivables [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Loans, allowance for credit losses		$ 1,129