Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 3,660	$ 3,680	$ 11,892	$ 13,586
Other comprehensive income (loss):
Unrealized holding gains (losses) on available for sale securities	86	(1,225)	1,993	2,273
Tax effect	(29)	417	(678)	(772)
Pension liability adjustment	426	83	946	249
Tax effect	(144)	(28)	(321)	(84)
Total other comprehensive income (loss)	339	(753)	1,940	1,666
Comprehensive income	$ 3,999	$ 2,927	$ 13,832	$ 15,252

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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