Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Comprehensive Income [Abstract]
Net Income	$ 22,783	$ 23,428	$ 26,177
Unrealized gains on available for sale securities:
Net change in unrealized gain (loss) on available-for-sale securities, net of tax of $10,982, $(1,851), and $(3,365)	(20,397)	3,439	6,248
Net reclassification adjustment for gains included in net income, net of tax of $275, $874, and $727	(510)	(1,624)	(1,349)
Net change in unrealized gains (losses) on available-for-sale securities, net of tax	(20,907)	1,815	4,899
Net change in unrealized gains (losses) on cash flow hedging derivatives, net of tax of $(2,510), $(32), and $3,530	4,663	59	(6,555)
Postretirement plans:
Net actuarial gain (loss), net of tax of $(391), $563, and $361	726	(1,046)	(671)
Reclassification of amortization of net unrecognized actuarial (gain) loss and of prior service cost included in net periodic cost, net of tax of $(94), $(56), and $(32)	174	108	59
Net gain (loss) on postretirement plans, net of tax	900	(938)	(612)
Other comprehensive income (loss)	(15,344)	936	(2,268)
Comprehensive Income	$ 7,439	$ 24,364	$ 23,909