Other Comprehensive Income/Loss (Components of Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments and Tax [Abstract]
Net unrealized holding gain (loss) on securities arising during the period, before tax amount	$ 4,873	$ (649)	$ 3,605	$ 11,242
Reclassification adjustment for gain on sales of securities included in net income, before tax amount	0	(141)	(72)	(141)
Net unrealized gain (loss) on securities available-for-sale	4,873	(790)	3,533	11,101
Other Comprehensive Income (Loss), Available-for-sale Securities, before Reclassification Adjustments, Tax [Abstract]
Net unrealized holding loss on securities arising during the period, income tax expense	(1,970)	229	(1,457)	(3,970)
Realization of prior year securities tax adjustment	0	50	29	50
Net unrealized loss on securities available-for-sale	(1,970)	279	(1,428)	(3,920)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax [Abstract]
Net unrealized gain (loss) on securities available-for-sale:	2,903	(420)	2,148	7,272
Reclassification adjustment for gain on sales of securities included in net income	0	(91)	(43)	(91)
Net unrealized gain (loss) on securities available-for-sale	2,903	(511)	2,105	7,181
Net actuarial loss adjustment on pension plans and other postretirement benefits before tax amount:
Reclassification adjustment for net actuarial loss on pension plans and other postretirement benefits included in net income	743	228	2,229	685
Reclassification adjustment for prior service cost on pension plans and other postretirement benefits included in net income	48	47	143	142
Total other comprehensive income, before tax amount	5,664	(515)	5,905	11,928
Net actuarial loss adjustment on pension plans and other postretirement benefits, tax expense:
Reclassification adjustment for net actuarial loss on pension plans and other postretirement benefits included in net income	(301)	(81)	(901)	(242)
Reclassification adjustment for prior service cost on pension plans and other postretirement benefits included in net income	(19)	(16)	(58)	(50)
Total other comprehensive income, tax expense	(2,290)	182	(2,387)	(4,212)
Net unrealized gain on securities available-for-sale:
Reclassification adjustment for net actuarial loss on pension plans and other postretirement benefits included in net income	442	147	1,328	443
Reclassification adjustment for prior service cost included in net income	29	31	85	92
Total other comprehensive income (loss), net of tax	$ 3,374	$ (333)	$ 3,518	$ 7,716