Note 5 - Credit Quality - Loans Modified as Troubled Debt Restructurings by Loan Class and Accrual Status (Details) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Nonaccrual	[1]	$ 1,814	$ 2,342
Accrual		10,248	6,575
TDRs		12,062	8,917
Allowance for loan losses related to TDRs		0	353
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Nonaccrual	[1]	0	0
Accrual		1,326	0
TDRs		1,326	0
Commercial Portfolio Segment [Member] | Single Family Non-owner Occupied [Member]
Nonaccrual	[1]	1,585	552
Accrual		1,265	595
TDRs		2,850	1,147
Commercial Portfolio Segment [Member] | Non-farm, Non-residential [Member]
Nonaccrual	[1]	0	0
Accrual		2,407	307
TDRs		2,407	307
Consumer Real Estate Portfolio Segment [Member] | Home Equity Lines [Member]
Nonaccrual	[1]	0	0
Accrual		77	115
TDRs		77	115
Consumer Real Estate Portfolio Segment [Member] | Single Family Owner Occupied [Member]
Nonaccrual	[1]	229	1,790
Accrual		4,927	5,305
TDRs		5,156	7,095
Consumer Real Estate Portfolio Segment [Member] | Owner Occupied Construction [Member]
Nonaccrual	[1]	0	0
Accrual		216	221
TDRs		216	221
Consumer and Other Portfolio Segment [Member]
TDRs			32
Consumer and Other Portfolio Segment [Member] | Consumer Loans [Member]
Nonaccrual	[1]	0	0
Accrual		30	$ 32
TDRs		$ 30

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