Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 7,833	$ 9,669
Other comprehensive income, net of reclassification adjustment:
Unrealized holding gains on available for sale securities	3,743	6,142
Tax effect	(786)	(1,289)
Pension liability adjustment	73	147
Tax effect	(16)	(31)
Total other comprehensive income	3,014	4,969
Comprehensive income	$ 10,847	$ 14,638

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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