Income Taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Allowance for loan losses	$ 799
Real estate owned	65	$ 5
Accrued liabilities	150	173
State income taxes	34	33
Stock compensation	165	182
Net operating loss carryforward	3,887	4,367
Non-accrual loan interest	3	4
Partnership investment	140	101
General business credit	1,661	1,458
Alternative minimum tax credit	151	256
Unrealized appreciation AFS	50
Other	28	14
Total deferred tax assets	7,133	6,593
Deferred tax liabilities:
Section 481 Adjustments to bad debts	(980)
Deferred loan fees/costs	(775)	(817)
Allowance for loan losses		(276)
Basis difference on fixed assets	(35)	(49)
Net unrealized appreciation on available-for-sale securities		(36)
FHLB stock dividends	(266)	(266)
Mortgage servicing rights	(5)	(7)
Prepaid expenses	(27)	(32)
Total deferred tax liabilities	(2,088)	(1,483)
Net deferred tax assets	$ 5,045	5,110
Valuation allowance
Period for which prior cumulative losses considered in assessing the realization of deferred tax assets	2 years
Valuation allowance	$ 0	$ 0