Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 3,014	$ 3,596	$ 10,003	$ 8,231
Other comprehensive income (loss):
Unrealized holding gains (losses) on available for sale securities	(684)	1,454	(3,898)	1,905
Tax effect	143	(495)	818	(647)
Pension liability adjustment	143	426	286	520
Tax effect	(30)	(145)	(60)	(177)
Total other comprehensive income (loss)	(428)	1,240	(2,854)	1,601
Comprehensive income	$ 2,586	$ 4,836	$ 7,149	$ 9,832

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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