Other Comprehensive Income/Loss (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net unrealized loss on securities available-for-sale before tax amount:
Net unrealized holding loss on securities available-for-sale arising during the period	$ (1,984)		$ (12,180)
Reclassification adjustment for gain on sales of securities included in net income			(2,057)
Net unrealized loss on securities available-for-sale			(14,237)
Net unrealized loss on securities available-for-sale, tax benefit (expense):
Net unrealized holding loss on securities available-for-sale arising during the period	698		4,291
Reclassification adjustment for gain on sales of securities included in net income			725
Net unrealized loss on securities available-for-sale			5,016
Net unrealized loss on securities available-for-sale:
Net unrealized holding loss on securities available-for-sale arising during the period	(1,286)	(3,796)	(7,889)	(3,194)
Reclassification adjustment for gain on sales of securities included in net income			(1,332)	(1,604)
Net unrealized loss on securities available-for-sale	(1,286)	(3,796)	(9,221)	(4,798)
Reclassification adjustment for net actuarial loss included in net income, Before Tax Amount	903		2,708
Reclassification adjustment for net actuarial loss included in net income, Tax Benefit (Expense)	(318)		(954)
Reclassification adjustment for net actuarial loss included in net income, After Tax Amount	585	448	1,754	3,077
Reclassification adjustment for prior service cost included in net income, Before Tax Amount	53		159
Reclassification adjustment for prior service cost included in net income, Tax Benefit (Expense)	(19)		(56)
Reclassification adjustment for prior service cost included in net income, After Tax Amount	34	32	103	67
Other Comprehensive loss, Before Tax Amount	(1,028)		(11,370)
Other Comprehensive loss, Tax Benefit (Expense)	361		4,006
Total other comprehensive (loss) income, net of tax	$ (667)	$ (3,260)	$ (7,364)	$ 19,246