Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 7,708	$ (3,433)	$ 26,038	$ 6,570
Other comprehensive income (loss), net of reclassification adjustment:
Unrealized holding gains (losses) on available for sale securities	3,724	(935)	16,164	(4,833)
Tax effect	(782)	197	(3,393)	1,015
Pension liability adjustment	147	143	441	429
Tax effect	(31)	(30)	(93)	(90)
Total other comprehensive income (loss)	3,058	(625)	13,119	(3,479)
Comprehensive income (loss)	$ 10,766	$ (4,058)	$ 39,157	$ 3,091

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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