Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 10,783	$ 10,057	$ 32,368	$ 31,483
Other comprehensive income (loss):
Change in net unrealized holding gains (losses) on available-for-sale securities	848	(2,271)	16,479	(17,099)
Change in funded status of pension plan	88		264
Change in net unrealized gain (loss) on derivative instruments	(276)	687	(4,334)	281
Other comprehensive income (loss) before income taxes	660	(1,584)	12,409	(16,818)
Income tax expense (benefit)	197	(479)	3,764	(5,081)
Other comprehensive income (loss)	463	(1,105)	8,645	(11,737)
Comprehensive income	$ 11,246	$ 8,952	$ 41,013	$ 19,746

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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