Allowance for Loan Losses and Reserve for Unfunded Lending Commitments - Changes In Allowance for Loan Losses and Reserve for Unfunded Lending Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Loan Losses
Balance, beginning of year	$ 13,603	$ 12,801	$ 12,601
Provision for (recovery of) loan losses	(103)	1,016	250
Charge-offs	(1,020)	(690)	(326)
Recoveries	325	476	276
Balance, end of year	12,805	13,603	12,801
Reserve for Unfunded Lending Commitments
Balance, beginning of year	206	203	184
Provision for unfunded commitments	11	3	19
Charge-offs	0	0	0
Balance, end of year	$ 217	$ 206	$ 203