Accumulated Other Comprehensive Loss (Reclassification out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gains	$ 41	$ 14
Tax (expense) benefit	(522)	(877)
Net income	1,755	3,151
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	(312)	(240)
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	49
Tax (expense) benefit	(13)	(13)
Net income	37	36
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		(6)
Tax (expense) benefit		2
Net income		(4)
Investment Securities HTM [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income expense securities taxable	(72)	(75)
Tax (expense) benefit	19	20
Net income	(53)	(55)
Pension Plan [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax (expense) benefit	96	73
Net income	(262)	(196)
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	(358)	(269)
SERP [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax (expense) benefit	12	7
Net income	(34)	(21)
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	(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