CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 32,937	$ 25,993	$ 14,933
Other comprehensive income (loss), before tax:
Changes in unrealized loss on securities available for sale	(8,563)	528	(12,059)
Changes in unrealized loss on derivative hedges	654	(838)	(272)
Changes in unrealized loss on post-retirement plans	(216)	(328)	90
Income taxes related to other comprehensive income (loss):
Changes in unrealized loss on securities available for sale	1,978	(114)	4,221
Changes in unrealized loss on derivative hedges	(168)	386	95
Changes in unrealized loss on post-retirement plans	47	138	(30)
Total other comprehensive loss	(6,268)	(228)	(7,955)
Total comprehensive income	$ 26,669	$ 25,765	$ 6,978

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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