CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 39,634	$ 24,136	$ 76,313	$ 47,329
Other comprehensive income (loss), net of tax:
Unrealized holding gain (loss) on securities available for sale arising during the period, net of tax of $683, $3,033, $4,874 and $8,476	(2,570)	5,632	(20,268)	15,741
Unrealized gain on cash flow hedges arising during the period, net of tax of $61, $142, $167 and $131	230	(262)	874	(239)
Reclassification adjustment for net gains included in net income, net of tax of $214, $110, $516 and $226	(803)	(206)	(1,940)	(420)
Defined benefit pension plan amortization of prior service cost, net of tax of $31 and $63	0	(58)	0	(117)
Total other comprehensive income (loss), net of tax	(3,143)	5,106	(21,334)	14,965
Comprehensive income	$ 36,491	$ 29,242	$ 54,979	$ 62,294