Consolidated Statements of Comprehensive Income (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
Net income	$ 6,646	$ 5,588	$ 12,322	$ 8,688
Unrealized gains (losses) on securities available for sale:
Unrealized holding gains (losses) arising during the period, pretax	749	(1,853)	1,052	(2,159)
Tax (expense) benefit	(292)	723	(410)	841
Reclassification to realized gains	(786)	(7)	(786)	(7)
Tax expense	306	3	306	3
Postretirement Plans:
Amortization of unrecognized net actuarial (gain) loss	(56)	15	(110)	18
Tax expense (benefit)	33	(6)	66	(7)
Other comprehensive income (loss)	(46)	(1,125)	118	(1,311)
Comprehensive income	$ 6,600	$ 4,463	$ 12,440	$ 7,377

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