CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 24,358	$ 21,059	$ 71,687	$ 58,758
Other comprehensive income net of tax:
Unrealized holding gain (loss) on securities available for sale arising during the period, net of tax of $4,101, $1,627, $4,374 and $4,234	(7,617)	(3,022)	8,124	7,863
Unrealized gain (loss) on cash flow hedges arising during the period, net of tax of $3, $134, $134 and $835	(7)	250	(246)	(1,548)
Reclassification adjustment for net gains included in net income, net of tax of $32, $183, $258 and $554	(60)	(339)	(480)	(1,029)
Defined benefit pension plan amortization of prior service cost, net of tax of $31 and $94	(58)		(175)
Period change	(7,742)	(3,111)	7,223	5,286
Comprehensive income	$ 16,616	$ 17,948	$ 78,910	$ 64,044