Note 4 - Loans - Age Analysis of Past Due Loans and Nonaccrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Loans	$ 935,271	$ 782,027	$ 766,796
Financial Asset Originated [Member]
Accruing loans past due	3,788	8,234
Nonaccrual loans	9,571	9,482
Current loans	782,686	745,924
Loans	796,045	763,640
Financial Assets Acquired [Member]
Accruing loans past due	203
Nonaccrual loans	180
Current loans	138,843	18,387
Loans	139,226	18,387
Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	3,786	8,234
Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due	203
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	2
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member]
Loans	68,535	57,410	45,029
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financial Asset Originated [Member]
Accruing loans past due	365	282
Nonaccrual loans	442	637
Current loans	42,754	49,262
Loans	43,561	50,181
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financial Assets Acquired [Member]
Accruing loans past due	178
Nonaccrual loans	43
Current loans	24,753	7,229
Loans	24,974	7,229
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	365	282
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due	178
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Commercial and Agricultural Portfolio Segment [Member] | Commercial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member]
Loans	18,861	16,799	20,037
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financial Asset Originated [Member]
Accruing loans past due		117
Nonaccrual loans	1,304	413
Current loans	17,257	15,463
Loans	18,561	15,993
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans
Current loans	300	806
Loans	300	806
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due		117
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Commercial and Agricultural Portfolio Segment [Member] | Agricultural [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial [Member]
Loans	433,816	373,534	352,063
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financial Asset Originated [Member]
Accruing loans past due	822	679
Nonaccrual loans	1,849	2,966
Current loans	373,392	363,147
Loans	376,063	366,792
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans
Current loans	57,753	6,742
Loans	57,753	6,742
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	822	679
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial Construction [Member]
Loans	72,978	47,849	48,909
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financial Asset Originated [Member]
Accruing loans past due	123	88
Nonaccrual loans	36	463
Current loans	60,790	46,058
Loans	60,949	46,609
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans	69
Current loans	11,960	1,240
Loans	12,029	1,240
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	123	88
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Commercial Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential Construction [Member]
Loans	18,622	12,500	11,541
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financial Asset Originated [Member]
Accruing loans past due
Nonaccrual loans	354
Current loans	12,839	12,242
Loans	13,193	12,242
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans
Current loans	5,429	258
Loans	5,429	258
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential [Member]
Loans	205,188	187,714	187,591
Real Estate Portfolio Segment [Member] | Residential [Member] | Financial Asset Originated [Member]
Accruing loans past due	2,276	6,882
Nonaccrual loans	2,786	2,734
Current loans	172,121	176,083
Loans	177,183	185,699
Real Estate Portfolio Segment [Member] | Residential [Member] | Financial Assets Acquired [Member]
Accruing loans past due	9
Nonaccrual loans	25
Current loans	27,971	2,015
Loans	28,005	2,015
Real Estate Portfolio Segment [Member] | Residential [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	2,276	6,882
Real Estate Portfolio Segment [Member] | Residential [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due	9
Real Estate Portfolio Segment [Member] | Residential [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Residential [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Farmland [Member]
Loans	74,272	62,709	67,867
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financial Asset Originated [Member]
Accruing loans past due	139	76
Nonaccrual loans	2,669	2,052
Current loans	67,605	60,546
Loans	70,413	62,674
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans	39
Current loans	3,820	35
Loans	3,859	35
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	139	76
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Real Estate Portfolio Segment [Member] | Farmland [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Consumer and Other Portfolio Segment [Member] | Consumer [Member]
Loans	23,066	18,485	18,746
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financial Asset Originated [Member]
Accruing loans past due	63	110
Nonaccrual loans	131	213
Current loans	17,666	18,100
Loans	17,860	18,423
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financial Assets Acquired [Member]
Accruing loans past due	16
Nonaccrual loans	4
Current loans	5,186	62
Loans	5,206	62
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	61	110
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due	16
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due	2
Consumer and Other Portfolio Segment [Member] | Consumer [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Consumer and Other Portfolio Segment [Member] | Other [Member]
Loans	19,933	5,027	$ 15,013
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financial Asset Originated [Member]
Accruing loans past due
Nonaccrual loans		4
Current loans	18,262	5,023
Loans	18,262	5,027
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Nonaccrual loans
Current loans	1,671
Loans	1,671
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financing Receivables, 30-89 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Asset Originated [Member]
Accruing loans past due
Consumer and Other Portfolio Segment [Member] | Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Financial Assets Acquired [Member]
Accruing loans past due