Accumulated Other Comprehensive Loss (Reclassification out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains	$ 1,176			$ 40			$ 2,011	$ 84
Tax (expense) benefit	(1,396)			(938)			(2,629)	(2,605)
Net income	4,960	$ 2,570	$ 1,755	4,493	$ 2,602	$ 3,151	9,285	10,247
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	108			(238)			(870)	(717)
Investment securities- with OTTI [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income expense securities taxable	50			50			151	149
Tax (expense) benefit	(13)			(13)			(40)	(39)
Net income	37			37			111	110
Investment Securities -All Other AFS [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains	575			1			622	1
Tax (expense) benefit	(154)						(167)
Net income	421			1			455	1
Investment Securities HTM [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains							60
Interest income expense securities taxable	(74)			(82)			(809)	(243)
Tax (expense) benefit	20			22			201	65
Net income	(54)			(60)			(548)	(178)
Pension Plan [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	(358)			(269)
Tax (expense) benefit	96			73			288	219
Net income	(262)			(196)			(786)	(588)
Pension Plan [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Amortization of Unrecognized Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other expense							(1,074)	(807)
SERP [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax (expense) benefit	12			8			37	23
Net income	(34)			(20)			(102)	(62)
SERP [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Amortization of Unrecognized Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other expense							(141)	(87)
Salaries and employee benefits	(47)			(29)
SERP [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Amortization of Prior Service Costs [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	$ 1			$ 1			$ 2	$ 2