Accumulated Other Comprehensive Loss (Components of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	$ (656)	$ 402	$ 1,336	$ 2,884
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	72	(239)	(972)	(1,040)
Unrealized net actuarial loss, Net of Tax	1,647	121	131	2,957
Other Comprehensive Income, Before Tax Amount	2,221		156	5,364
Other Comprehensive Income, Tax (Expense) Benefit	(589)		(36)	(1,454)
Other Comprehensive (loss) Income, Net	1,632		120	3,910
Investment securities- with OTTI [Member]
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Before Tax Amount	708	(1,126)	(1,249)	(1,401)
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, tax effect	(190)	306	335	380
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Net of Tax	518	(820)	(914)	(1,021)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Before Tax Amount	50	50	151	149
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Tax Effect	(13)	(13)	(40)	(39)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Net of Tax	37	37	111	110
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Before Tax Amount	658	(1,176)	(1,400)	(1,550)
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Tax Effect	(177)	319	375	419
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Net of Tax	481	(857)	(1,025)	(1,131)
Investment Securities -All Other AFS [Member]
Securities: Unrealized holding gains (losses), Before Tax	(321)	552	2,446	3,957
Securities: Unrealized holding gains (losses), Tax Effect	86	(149)	(655)	(1,072)
Securities: Unrealized holding gains (losses), Net of Tax	(235)	403	1,791	2,885
Less: amortization recognized in income, Before Tax	575	1	622	1
Less: amortization recognized in income, Tax Effect	(154)		(167)
Less: amortization recognized in income, Net of Tax	421	1	455	1
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Before Tax	(896)	551	1,824	3,956
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Tax Effect	240	(149)	(488)	(1,072)
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	(656)	402	1,336	2,884
Investment Securities HTM [Member]
Less: amortization recognized in income, Before Tax			60
Less: amortization recognized in income, Tax Effect			(16)
Less: amortization recognized in income, Net of Tax			44
Held to maturity securities: Net unrealized gains on all HTM securities, Before tax	74	82	749	243
Held to maturity securities: Net unrealized gains on all HTM securities, Tax	(20)	(22)	(201)	(65)
Held to maturity securities: Net unrealized gains on all HTM securities, After tax	54	60	548	178
Investment Securities HTM [Member] | Amortization of Recognized Income [Member]
Less: amortization recognized in income, Before Tax	(74)	(82)	(809)	(243)
Less: amortization recognized in income, Tax Effect	20	22	217	65
Less: amortization recognized in income, Net of Tax	(54)	(60)	(592)	(178)
Cash Flow Hedge (OCI) [Member]
Cash flow hedges: Unrealized holding (losses) gains, Before Tax	90	(329)	(1,335)	(1,427)
Cash flow hedges: Unrealized holding (losses) gains, Tax Effect	(18)	90	363	387
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	72	(239)	(972)	(1,040)
Pension Plan [Member]
Unrealized net actuarial loss, Before Tax	1,891	(103)	(895)	3,250
Unrealized net actuarial loss, Tax Effect	(506)	28	240	(881)
Unrealized net actuarial loss, Net of Tax	1,385	(75)	(655)	2,369
Net plan liability adjustment, Before Tax	2,249	166	179	4,057
Net plan liability adjustment, Tax Effect	(602)	(45)	(48)	(1,100)
Net plan liability adjustment, Net of Tax	1,647	121	131	2,957
Pension Plan [Member] | Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(358)	(269)	(1,074)	(807)
Less: amortization of unrecognized loss, Tax Effect	96	73	288	219
Less: amortization of unrecognized loss, Net of Tax	(262)	(196)	(786)	(588)
SERP [Member]
Net plan liability adjustment, Before Tax	46	28	139	85
Net plan liability adjustment, Tax Effect	(12)	(8)	(37)	(23)
Net plan liability adjustment, Net of Tax	34	20	102	62
Other Comprehensive Income, Before Tax Amount		(678)
Other Comprehensive Income, Tax (Expense) Benefit		185
Other Comprehensive (loss) Income, Net		(493)
SERP [Member] | Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(47)	(29)	(141)	(87)
Less: amortization of unrecognized loss, Tax Effect	13	8	38	23
Less: amortization of unrecognized loss, Net of Tax	(34)	(21)	(103)	(64)
SERP [Member] | Amortization of Prior Service Costs [Member]
Less: amortization of prior service costs, Before Tax	1	1	2	2
Less: amortization of prior service costs, Tax Effect	$ (1)		(1)
Less: amortization of prior service costs, Net of Tax		$ 1	$ 1	$ 2