Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 33,117	$ 23,912	$ 20,549
Change in fair value of derivative instruments:
Change in fair value of derivative instruments for the period	1,404	9	195
Income tax effect	(491)	(3)	(68)
Changes from derivative instruments	913	6	127
Change in securities:
Unrealized appreciation (depreciation) for the period on AFS securities	2,110	(5,091)	(2,910)
Amortization from transfer of securities from available for sale to held to maturity securities	(256)	(653)	(549)
Reclassification adjustment for securities (gains) losses realized in income	(38)	(1,836)	(189)
Income tax effect	(636)	2,653	1,277
Unrealized gains (losses) on securities	1,180	(4,927)	(2,371)
Other Comprehensive Income (Loss), Net of Tax	2,093	(4,921)	(2,244)
Comprehensive Income	$ 35,210	$ 18,991	$ 18,305

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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