Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Other comprehensive income, before tax:
Amortization of net loss and prior service credit on pension and post retirement plans, before tax cost	$ (8)	$ (101)	$ (89)	$ (202)
Unrealized net holding gain on securities available-for-sale arising during the period, before tax gain	12,535	4,144	12,810	7,674
Reclassification adjustment for net gain realized in net income during the year, before tax gain	$ 851	$ 1,537	$ 1,138	$ 1,541
Cash dividend declared, per share (in dollars per share)	$ 0.0656	$ 0.0625	$ 0.1312	$ 0.1250
Sale of treasury stock (in shares)	122,795	112,016	236,700	221,825