Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands		Sep. 30, 2020	Dec. 31, 2019
Non-impaired gross loans		$ 797,804	$ 728,738
Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans		36,994	42,303
Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		178,302	180,713
Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans		389,817	361,765
Commercial Non Real Estate Segment [Member]
Non-impaired gross loans		100,045	45,658
Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans		33,611	34,535
Pass [Member]
Non-impaired gross loans	[1]	796,895	727,642
Pass [Member] | States Political Subdivisions [Member]
Non-impaired gross loans	[1]	59,035	63,764
Classified Excluding Impaired [Member]
Non-impaired gross loans	[1]	573	961
Special Mention [Member]
Non-impaired gross loans	[1]	336	135
Construction, 1-4 Family Residential [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	[1]	7,052	7,590
Construction, Other [Member] | Pass [Member] | Real Estate Construction Portfolio Segment[Member]
Non-impaired gross loans	[1]	29,942	34,713
Equity Lines [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	14,710	16,435
Equity Lines [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	19
Closed End First Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		87,555	94,814
Closed End First Liens [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		344	517
Closed End First Liens [Member] | Special Mention [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		67
Closed End Junior Liens [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans		3,530	3,861
Investor Owned Residential Real Estate [Member] | Pass [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	72,077	65,063
Investor Owned Residential Real Estate [Member] | Classified Excluding Impaired [Member] | Consumer Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]		23
Multifamily Real Estate [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	83,413	87,934
Multifamily Real Estate [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]		94
Multifamily Real Estate [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	269
Commercial Real Estate, Owner Occupied [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	152,188	127,937
Commercial Real Estate, Owner Occupied [Member] | Classified Excluding Impaired [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	143	164
Commercial Real Estate Other [Member] | Pass [Member] | Commercial Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	153,804	145,636
Commercial and Industrial [Member] | Pass [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	[1]	99,984	45,387
Commercial and Industrial [Member] | Classified Excluding Impaired [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	[1]	61	136
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Non Real Estate Segment [Member]
Non-impaired gross loans	[1]		135
Credit Card Receivable [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	4,676	5,703
Automobile Loan [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	12,620	14,810
Automobile Loan [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]		19
Other Consumer Loans [Member] | Pass [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	16,309	13,995
Other Consumer Loans [Member] | Classified Excluding Impaired [Member] | Consumer Non Real Estate Portfolio Segment [Member]
Non-impaired gross loans	[1]	$ 6	$ 8

[1] Excludes impaired, if any.