Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	$ 191,628	$ 150,727
Commitments outstanding for capital expenditures	255
Commercial loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	36,896	18,964
Other loans [Member] | Fixed rate [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	3,649	2,747
Other loans [Member] | Adjustable rate [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	1,456	1,150
Unused lines of credit [Member] | Fixed rate [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	19,350	20,984
Unused lines of credit [Member] | Adjustable rate [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	113,699	90,147
Unused overdraft protection amounts on demand and NOW accounts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	16,319	16,441
Standby letters of credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks, liability	$ 259	$ 294