Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statements Of Comprehensive Income [Abstract]
Net income	$ 9,133	$ 7,729	$ 18,214	$ 15,364
Other comprehensive income:
Change in net unrealized holding gains on available-for-sale securities	4,280	5,511	5,351	10,653
Change in funded status of pension plan	4	61	9	122
Other comprehensive income before income taxes	4,284	5,572	5,360	10,775
Income tax expense	1,798	2,335	2,250	4,607
Other comprehensive income	2,486	3,237	3,110	6,168
Comprehensive income	$ 11,619	$ 10,966	$ 21,324	$ 21,532

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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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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