Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 7,097	$ 6,480
Net change in fair value of interest rate swap agreements designated as cash flow hedges:
Unrealized gain on interest rate swaps, net of tax of ($4) and ($3), respectively	16	6
Reclassification adjustment for losses recognized in earnings, net of tax of ($12) and ($27), respectively	46	49
Net change in fair value of interest rate swap agreements designated as cash flow hedges	62	55
Unrealized gains on other-than-temporarily impaired securities available for sale:
Unrealized gains arising during the period, net of tax of $0 and ($47), respectively	0	87
Reclassification adjustment for realized gains included in net income, net of tax of $0 and $484, respectively	0	(899)
Unrealized gains on other-than-temporarily impaired securities available for sale net of reclassification adjustment for realized gains (losses) included in net income	0	(812)
Unrealized gains on other securities available for sale:
Unrealized (losses) gains arising during the period, net of tax of $1,053 and ($456), respectively	(3,964)	850
Other comprehensive income (loss)	(3,902)	93
COMPREHENSIVE INCOME	$ 3,195	$ 6,573