Stockholders' Equity (Accumulated Other Comprehensive (Loss) Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders' Equity Attributable to Parent [Abstract]
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	$ 1,186	$ 0	$ 0	$ 0
Accumulated Other Comprehensive (Loss) Income
Unrealized (Loss) Gain on Securities	2,869	2,542	(9,761)
Unrealized (Loss) Gain on Securities	(2,288)	327	12,303
Unrealized (Loss) Gain on Securities	581	2,869	2,542
Unrecognized Net Pension and Postretirement Costs	(3,228)	(3,483)	(3,483)
Unrecognized Net Pension and Postretirement Costs	(93)	615	(360)
Unrecognized Net Pension and Postretirement Costs	(3,321)	(3,228)	(3,483)
Accumulated Other Comprehensive (Loss) Income	(359)	(1,301)	(13,244)
Accumulated Other Comprehensive (Loss) Income	(1,195)	942	11,943
Accumulated Other Comprehensive (Loss) Income	(1,554)	(359)	(1,301)
Realized gain on sale of securities, net of tax	(604)	(474)	(259)
Other Comprehensive Income (Loss), Reclassification Adjustment in Net Income, Net of Tax		(474)	(259)
Realized loss due to settlement and curtailment, net of tax		298	910
Realized loss due to settlement and curtailment, net of tax		298	910
Other comprehensive (loss) income, net of reclassifications and tax	(1,684)	801	12,562
Other comprehensive (loss) income, net of reclassifications and tax	(93)	317	(1,270)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	1,186	0	0
Other comprehensive (loss) income, net of reclassifications and tax	$ (1,777)	$ 1,118	$ 11,292