Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 12,170	$ 6,246	$ 21,458	$ 14,189
Other comprehensive (loss) income, net of tax:
Securities available for sale and transferred securities	(2,487)	1,722	(8,757)	2,316
Hedging derivative instruments	227		123
Pension and post-retirement obligations	127	171	254	342
Total other comprehensive (loss) income, net of tax	(2,133)	1,893	(8,380)	2,658
Comprehensive income	$ 10,037	$ 8,139	$ 13,078	$ 16,847

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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