Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Consolidated Statements of Comprehensive Income (Unaudited) [Abstract]
Net income	$ 11,808	$ 9,763	$ 22,819	$ 18,931
Net unrealized holding gain (loss) on securities available for sale	11,429	(26,315)	18,884	(29,254)
Reclassification adjustments for net gain recognized in income	0	(1,432)	(6)	(1,434)
Tax effect	(4,517)	11,064	(7,543)	12,237
Net unrealized gain (loss) on securities available for sale, net of tax	6,912	(16,683)	11,335	(18,451)
Amortization of net actuarial (gain) loss	(74)	101	(146)	233
Amortization of prior service credit	(45)	(65)	(90)	(131)
Tax effect	48	(15)	93	(40)
Amortization of net actuarial (gain) loss and prior service credit on pension and postretirement plans, net of tax	(71)	21	(143)	62
Other comprehensive income (loss), net of tax	6,841	(16,662)	11,192	(18,389)
Comprehensive income (loss)	$ 18,649	$ (6,899)	$ 34,011	$ 542