Income Taxes, Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets [Abstract]
Allowance for loan losses	$ 4,027	$ 3,543
Deferred compensation	116	125
Retirement compensation	1,313	1,273
Stock option compensation	127	67
Postretirement benefits	472	565
Current state franchise taxes	470	381
Non-accrual interest	118	41
Low income housing tax credit partnership	128	0
Other	282	129
Sale-Leaseback	100	124
Investment securities unrealized loss	1,560	1,209
Deferred tax assets	8,713	7,457
Deferred tax liabilities [Abstract]
Fixed assets depreciation	1,478	1,461
FHLB dividends	187	187
Tax credit - loss on pass-through	0	176
Deferred loan costs	806	941
Mortgage servicing rights	142	129
Other	84	15
Total deferred tax liabilities	2,697	2,909
Net deferred tax assets (see Note 7)	$ 6,016	$ 4,548