Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Other service charges and fees													$ 4,173	$ 3,878	$ 3,713
(Loss) on the sale and disposal of bank premises and equipment													(3)	(12)	(10)
Gain (loss) on sale of securities													17	(10)	98
Other operating income													114	463	285
Total noninterest income	$ 1,609	$ 1,804	$ 1,665	$ 1,801	$ 1,892	$ 1,617	$ 1,598	$ 1,673	$ 1,609	$ 1,687	$ 1,738	$ 1,635	6,879	6,780	6,669
Trust asset management fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													1,360	1,238	1,356
Overdrawn account fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													995	999	1,003
Monthly and other service charges
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													223	224	224
Interchange fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													361	331	296
ATM fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													2,240	2,046	2,056
Brokerage commissions (1)
Disaggregation of Revenue [Line Items]
Other service charges and fees													831	865	744
Other charges and fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													671	583	565
Other service charges and fees													741	636	617
Other operating income
Disaggregation of Revenue [Line Items]
Revenue from contract with customer													$ 153	$ 190	$ 159