Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated other comprehensive income (loss), beginning balance	$ (28,309)
Net other comprehensive income (loss)	17,072	$ (4,799)	$ 472
Reclassification of income tax effects due to the adoption of ASU 2018-02			0
Accumulated other comprehensive income (loss), ending balance	(11,237)	(28,309)
Net Unrealized Gains (Losses) on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance	(16,762)	(7,534)	(6,825)
Other comprehensive income (loss) before reclassifications, net of tax	19,947	(9,228)	621
Amounts reclassified from accumulated other comprehensive income, net of tax	41	0	0
Net other comprehensive income (loss)	19,988	(9,228)	621
Reclassification of income tax effects due to the adoption of ASU 2018-02			(1,330)
Accumulated other comprehensive income (loss), ending balance	3,226	(16,762)	(7,534)
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance	191	(428)	(300)
Other comprehensive income (loss) before reclassifications, net of tax	(1,105)	488	(551)
Amounts reclassified from accumulated other comprehensive income, net of tax	121	131	499
Net other comprehensive income (loss)	(984)	619	(52)
Reclassification of income tax effects due to the adoption of ASU 2018-02			(76)
Accumulated other comprehensive income (loss), ending balance	(793)	191	(428)
Defined Benefit Pension Plan Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance	(11,738)	(15,548)	(12,632)
Other comprehensive income (loss) before reclassifications, net of tax	(2,838)	2,369	(741)
Amounts reclassified from accumulated other comprehensive income, net of tax	906	1,441	644
Net other comprehensive income (loss)	(1,932)	3,810	(97)
Reclassification of income tax effects due to the adoption of ASU 2018-02			(2,819)
Accumulated other comprehensive income (loss), ending balance	(13,670)	(11,738)	(15,548)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss), beginning balance	(28,309)	(23,510)	(19,757)
Other comprehensive income (loss) before reclassifications, net of tax	16,004	(6,371)	(671)
Amounts reclassified from accumulated other comprehensive income, net of tax	1,068	1,572	1,143
Net other comprehensive income (loss)	17,072	(4,799)	472
Reclassification of income tax effects due to the adoption of ASU 2018-02			(4,225)
Accumulated other comprehensive income (loss), ending balance	$ (11,237)	$ (28,309)	$ (23,510)