Consolidated Statements of Comprehensive Income (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Other Comprehensive Income [Abstract]
Net income	$ 3,726	$ 3,941	$ 10,101	$ 8,379
Unrealized gains on securities available for sale:
Unrealized holding gains arising during the period, pretax	1,198	1,190	1,387	2,085
Tax benefit	(467)	(464)	(541)	(813)
Reclassification to realized gains	(60)	(15)	(74)	(24)
Tax expense	23	5	29	9
Postretirement Plans:
Amortization of unrecognized net actuarial loss	140	117	280	234
Tax expense	(56)	(46)	(112)	(92)
Amortization of prior service cost and transition obligation	9	9	18	18
Tax expense	(4)	(4)	(8)	(8)
Other comprehensive income	783	792	979	1,409
Comprehensive income	$ 4,509	$ 4,733	$ 11,080	$ 9,788

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