Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accumulated other comprehensive income (loss), beginning balance			$ (23,510)	$ (19,757)
Other comprehensive income (loss) before reclassifications			(12,466)	1,680
Amounts reclassed from accumulated other comprehensive income (loss)			914	408
Total other comprehensive income (loss), net of tax	$ (2,387)	$ 1,376	(11,552)	2,088
Accumulated other comprehensive income (loss), ending balance	(35,062)	(17,669)	(35,062)	(17,669)
Net Unrealized Gains (Losses) on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance			(7,534)	(6,825)
Other comprehensive income (loss) before reclassifications			(13,526)	2,229
Amounts reclassed from accumulated other comprehensive income (loss)			0	0
Total other comprehensive income (loss), net of tax			(13,526)	2,229
Accumulated other comprehensive income (loss), ending balance	(21,060)	(4,596)	(21,060)	(4,596)
Net Unrealized Losses on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance			(428)	(300)
Other comprehensive income (loss) before reclassifications			1,060	(549)
Amounts reclassed from accumulated other comprehensive income (loss)			194	199
Total other comprehensive income (loss), net of tax			1,254	(350)
Accumulated other comprehensive income (loss), ending balance	826	(650)	826	(650)
Pension Benefit Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance			(15,548)	(12,632)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassed from accumulated other comprehensive income (loss)			720	209
Total other comprehensive income (loss), net of tax			720	209
Accumulated other comprehensive income (loss), ending balance	$ (14,828)	$ (12,423)	$ (14,828)	$ (12,423)