Loans and Allowance for Loan Losses (Details 6) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary of consumer credit exposure
Total loans	$ 487,490	$ 419,768
Residential real estate
Summary of consumer credit exposure
Total loans	62,071	57,008
Consumer | Home equity
Summary of consumer credit exposure
Total loans	26,018	25,061
Consumer | Other
Summary of consumer credit exposure
Total loans	2,925	2,726
Performing | Residential real estate
Summary of consumer credit exposure
Total loans	61,824	55,743
Performing | Consumer | Home equity
Summary of consumer credit exposure
Total loans	25,889	25,006
Performing | Consumer | Other
Summary of consumer credit exposure
Total loans	2,925	2,726
Nonperforming | Residential real estate
Summary of consumer credit exposure
Total loans	247	1,265
Nonperforming | Consumer | Home equity
Summary of consumer credit exposure
Total loans	$ 129	$ 55