Income Taxes - Reconciliation of income tax expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Computed "expected" tax expense	$ 2,753	$ 5,023
Increase (decrease) in income taxes resulting from:
State income tax benefit	(86)
Non-deductible expense	141	154
Tax free income	(112)	(328)
Tax benefits from exercise of stock options	(308)	(39)
Deferred tax asset adjustment for enacted change in tax rate		2,036
Other	(150)
Income Tax Expense (Benefit), Total	$ 2,238	$ 6,846