Comprehensive Income Changes in Accumulated Other Comprehensive Income By Component (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning of Period	$ (4,373)	[1]	$ (8,462)	[1]
Other comprehensive income, before reclassifications, net of tax	241	[1]	220	[1]
Reclassification from Accumulated Other Comprehensive Income, net of tax	57	[1]	(82)	[1]
Other Comprehensive (Loss) Income	298	[1]	138	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax, End of Period	(4,075)	[1]	(8,324)	[1]
Unrealized Gains and Losses on Available for Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning of Period	2,374	[1]	5,625	[1]
Other comprehensive income, before reclassifications, net of tax	241	[1]	220	[1]
Reclassification from Accumulated Other Comprehensive Income, net of tax	0	[1]	(318)	[1]
Other Comprehensive (Loss) Income	241	[1]	(98)	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax, End of Period	2,615	[1]	5,527	[1]
Amortization of Net Retirement Plan Actuarial Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning of Period	(6,697)	[1]	(14,036)	[1]
Other comprehensive income, before reclassifications, net of tax	0	[1]	0	[1]
Reclassification from Accumulated Other Comprehensive Income, net of tax	70	[1]	236	[1]
Other Comprehensive (Loss) Income	70	[1]	236	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax, End of Period	(6,627)	[1]	(13,800)	[1]
Accretion of Net Retirement Plan Prior Service Credit [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning of Period	(50)	[1]	(51)	[1]
Other comprehensive income, before reclassifications, net of tax	0	[1]	0	[1]
Reclassification from Accumulated Other Comprehensive Income, net of tax	(13)	[1]	0	[1]
Other Comprehensive (Loss) Income	(13)	[1]	0	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax, End of Period	$ (63)	[1]	$ (51)	[1]

[1] (1) All amounts are net of tax. Amounts in parentheses indicate debits.