Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated other comprehensive income (loss), beginning balance	$ (11,237)
Net other comprehensive income (loss)	3,846	$ 17,072	$ (4,799)
Accumulated other comprehensive income (loss), ending balance	(7,391)	(11,237)
Net Unrealized Gains (Losses) on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance	3,226	(16,762)	(7,534)
Other comprehensive income (loss) before reclassifications, net of tax	6,655	19,947	(9,228)
Amounts reclassified from accumulated other comprehensive income, net of tax	0	41	0
Net other comprehensive income (loss)	6,655	19,988	(9,228)
Accumulated other comprehensive income (loss), ending balance	9,881	3,226	(16,762)
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance	(793)	191	(428)
Other comprehensive income (loss) before reclassifications, net of tax	(1,521)	(1,105)	488
Amounts reclassified from accumulated other comprehensive income, net of tax	867	121	131
Net other comprehensive income (loss)	(654)	(984)	619
Accumulated other comprehensive income (loss), ending balance	(1,447)	(793)	191
Defined Benefit Pension Plan Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance	(13,670)	(11,738)	(15,548)
Other comprehensive income (loss) before reclassifications, net of tax	(3,896)	(2,838)	2,369
Amounts reclassified from accumulated other comprehensive income, net of tax	1,741	906	1,441
Net other comprehensive income (loss)	(2,155)	(1,932)	3,810
Accumulated other comprehensive income (loss), ending balance	(15,825)	(13,670)	(11,738)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss), beginning balance	(11,237)	(28,309)	(23,510)
Other comprehensive income (loss) before reclassifications, net of tax	1,238	16,004	(6,371)
Amounts reclassified from accumulated other comprehensive income, net of tax	2,608	1,068	1,572
Net other comprehensive income (loss)	3,846	17,072	(4,799)
Accumulated other comprehensive income (loss), ending balance	$ (7,391)	$ (11,237)	$ (28,309)