Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income	$ 23,070	$ 23,016	$ 21,742
Total other comprehensive loss	(850)	(612)	(684)
Comprehensive income	22,220	22,404	21,058
Unrealized gains losses on derivatives [Member]
Unrealized gains (losses) on derivatives arising during the period	(66)	882	(1,144)
Less: reclassification adjustment for net loss on derivatives realized in net income	304	464	89
Less: reclassification adjustment for amortization of derivative termination costs, realized in interest expense	109	109	71
Income tax (expense) benefit	(132)	(553)	374
Other comprehensive income (loss) on derivatives	215	902	(610)
Unrealized gains losses on securities [Member]
Unrealized holding gains arising during the period	(1,124)	(2,249)	(33)
Less: reclassification adjustment for net (gains) losses realized in net income	(326)	(66)	(47)
Less: reclassification adjustment for amortization of net unrealized gains on securities transferred from available for sale to held to maturity, realized in interest income	(268)	(128)	(39)
Income tax (expense) benefit	653	929	45
Other comprehensive income on available for sale securities, net of tax	$ (1,065)	$ (1,514)	$ (74)