Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 10,841	$ 11,111
Other comprehensive income (loss):
Change in net unrealized holding gains (losses) on available-for-sale securities	8,417	(11,734)
Change in funded status of pension plan	88
Change in net unrealized loss on derivative instruments	(1,545)
Other comprehensive income (loss) before income taxes	6,960	(11,734)
Income tax expense (benefit)	2,098	(3,548)
Other comprehensive income (loss)	4,862	(8,186)
Comprehensive income	$ 15,703	$ 2,925