Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 15,249	$ 16,301	$ 15,039
Other comprehensive loss:
Unrealized gains (losses) on securities available for sale	35	(5,736)	(1,785)
Tax effect	(12)	2,007	626
Reclassification adjustment for realized gains on securities	(812)	(836)	(867)
Tax effect	284	293	303
Change in unfunded pension liability	(234)	166	538
Tax effect	(82)	58	189
Other comprehensive loss	(657)	(4,164)	(1,374)
Comprehensive income	$ 14,592	$ 12,137	$ 13,665

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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