Note 5 - Credit Quality - Loans Modified as Troubled Debt Restructurings by Loan Class and Accrual Status (Details) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017
Nonaccrual	[1]	$ 2,581	$ 1,929
Accrual		6,427	7,734
TDRs		9,008	9,663
Allowance for loan losses related to TDRs		568	642
Commercial Portfolio Segment [Member] | Single Family Non-owner Occupied [Member]
Nonaccrual	[1]	640	364
Accrual		309	528
TDRs		949	892
Commercial Portfolio Segment [Member] | Non-farm, Non-residential [Member]
Nonaccrual	[1]
Accrual		314	295
TDRs		314	295
Consumer Real Estate Portfolio Segment [Member] | Home Equity Lines [Member]
Nonaccrual	[1]
Accrual		127	145
TDRs		127	145
Consumer Real Estate Portfolio Segment [Member] | Single Family Owner Occupied [Member]
Nonaccrual	[1]	1,941	1,565
Accrual		5,417	6,496
TDRs		7,358	8,061
Consumer Real Estate Portfolio Segment [Member] | Owner Occupied Construction [Member]
Nonaccrual	[1]
Accrual		225	233
TDRs		225	233
Consumer and Other Portfolio Segment [Member]
TDRs			37
Consumer and Other Portfolio Segment [Member] | Consumer Loans [Member]
Nonaccrual	[1]
Accrual		35	$ 37
TDRs		$ 35

[1] Nonaccrual TDRs are included in total nonaccrual loans disclosed in the nonaccrual table above.