Note 10 - Income Taxes - Components of Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Allowance for loan losses and unearned fee income	$ 1,773	$ 3,347
Valuation allowance on other real estate owned	156	237
Defined benefit plan	1,592	2,730
Deferred compensation and other liabilities	863	1,336
Discount accretion of securities		15
Net unrealized loss on securities available for sale	984	1,932
Total deferred tax assets	5,368	9,597
Deferred tax liabilities:
Fixed assets	(388)	(620)
Deposit intangibles	(1,059)	(1,573)
Defined benefit plan, prepaid portion	(1,579)	(1,345)
Discount accretion of securities	(2)
Total deferred tax liabilities	(3,028)	(3,538)
Net deferred tax assets	$ 2,340	$ 6,059