Stockholders' Equity (Accumulated Other Comprehensive (Loss) Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Unrealized (Loss) Gain on Securities, beginning balance	$ 6,892
Unrealized (Loss) Gain on Securities, current period change, net of tax	297
Unrealized (Loss) Gain on Securities, ending balance	6,917	6,892
Unrecognized Net Pension and Postretirement Costs, beginning balance	(6,238)
Unrecognized Net Pension and Postretirement Costs, current period change, net of tax	29	25
Unrecognized Net Pension and Postretirement Costs, ending balance	(6,209)	(6,238)
Accumulated Comprehensive (Loss) Income, beginning balance	654
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	(272)
Accumulated Comprehensive (Loss) Income, current period change, net of tax	326
Accumulated Comprehensive (Loss) Income, ending balance	$ 708	$ 654