Consolidated Condensed Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement of Comprehensive Income [Abstract]
Net Income	$ 20,034	$ 18,886	$ 40,744	$ 50,361
Other comprehensive income, net of tax:
Change in funded status of pension plan, net of income taxes of $222 for the three months ended June 30, 2012	0	0		412
Unrealized net holding gain on cash flow hedge, net of income taxes of $79 for the three months ended June 30, 2012 and $139 for the six months ended June 30, 2012	0	146		259
Unrealized net holding loss on securities available-for-sale, net of income taxes of $(11,058) and $1,511 for the three months ended June 30, 2013 and 2012 and $(12,340) and $326 for the six months ended June 30, 2013 and 2012, respectively	(20,537)	2,806	(22,916)	604
Other comprehensive income (loss)	(20,537)	2,952	(22,916)	1,275
Comprehensive income	$ (503)	$ 21,838	$ 17,828	$ 51,636