CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement Of Other Comprehensive Income [Abstract]
Net income	$ 6,768	$ 6,560
Securities available-for-sale
Unrealized holding (losses) gains arising during the period	(8,852)	1,020
Reclassification adjustments for net gains included in net income		(8)
Tax effect	2,395	(626)
Net of tax	(6,457)	386
Cash flow hedges
Unrealized holding gains arising during the period	4,070	(83)
Reclassification adjustments for (losses) gains included in net income	(61)	54
Tax effect	(1,116)	11
Net of tax	2,893	(18)
Total other comprehensive income (loss)	(3,564)	368
Comprehensive income	$ 3,204	$ 6,928

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 after tax and 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 after tax of other comprehensive income (loss) attributable to parent entity.

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