Other Comprehensive Income (Loss) (Schedule of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, Beginning Balance	$ (5,263)	$ 10,351
Other Comprehensive Income (Loss) Before Reclassification	2,412	(1,890)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(148)	(346)
Net Current Period Other Comprehensive Income (Loss)	2,264	(2,236)
Accumulated other comprehensive income, Ending Balance	(2,999)	8,115
Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, Beginning Balance	(5,231)	10,643
Other Comprehensive Income (Loss) Before Reclassification	2,412	(1,890)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	(148)	(346)
Net Current Period Other Comprehensive Income (Loss)	2,264	(2,236)
Accumulated other comprehensive income, Ending Balance	(2,967)	8,407
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, Beginning Balance	0	(231)
Other Comprehensive Income (Loss) Before Reclassification	0	0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0	0
Net Current Period Other Comprehensive Income (Loss)	0	0
Accumulated other comprehensive income, Ending Balance	0	(231)
Postretirement Benefit Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, Beginning Balance	(32)	(61)
Other Comprehensive Income (Loss) Before Reclassification	0	0
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	0	0
Net Current Period Other Comprehensive Income (Loss)	0	0
Accumulated other comprehensive income, Ending Balance	$ (32)	$ (61)