Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 9,669	$ 6,989
Other comprehensive income (loss), net of reclassification adjustment:
Unrealized holding gains (losses) on available for sale securities	6,142	(3,214)
Tax effect	(1,289)	675
Pension liability adjustment	147	143
Tax effect	(31)	(30)
Total other comprehensive income (loss)	4,969	(2,426)
Comprehensive income	$ 14,638	$ 4,563

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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