Accumulated Other Comprehensive Loss ("AOCL") (Components of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	$ 828	$ 2,748
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	(869)	(858)
Unrealized net actuarial loss, Net of Tax	(2,213)	(2,400)
Other Comprehensive Income, Before Tax Amount	(3,950)	(2,143)
Other Comprehensive Income, Tax (Expense) Benefit	1,058	575
Other Comprehensive (loss) Income, Net	(2,892)	(1,568)
Investment securities- with OTTI [Member]
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Before Tax Amount	(803)	(679)
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, tax effect	216	182
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Net of Tax	(587)	(497)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Before Tax Amount	202	200
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Tax Effect	(54)	(54)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Net of Tax	148	146
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Before Tax Amount	(1,005)	(879)
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Tax Effect	270	236
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Net of Tax	(735)	(643)
Investment Securities -All Other AFS [Member]
Securities: Unrealized holding gains (losses), Before Tax	1,765	3,753
Securities: Unrealized holding gains (losses), Tax Effect	(474)	(1,005)
Securities: Unrealized holding gains (losses), Net of Tax	1,291	2,748
Less: amortization recognized in income, Before Tax	632
Less: amortization recognized in income, Tax Effect	(169)
Less: amortization recognized in income, Net of Tax	463
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Before Tax	1,133	3,753
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Tax Effect	(305)	(1,005)
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	828	2,748
Investment Securities HTM [Member]
Less: amortization recognized in income, Before Tax	(798)	(317)
Less: amortization recognized in income, Tax Effect	214	85
Less: amortization recognized in income, Net of Tax	(584)	(232)
Held to maturity securities: Net unrealized gains on all HTM securities, Before tax	798	317
Held to maturity securities: Net unrealized gains on all HTM securities, Tax	(214)	(85)
Held to maturity securities: Net unrealized gains on all HTM securities, After tax	584	232
Cash Flow Hedge (OCI) [Member]
Cash flow hedges: Unrealized holding (losses) gains, Before Tax	(1,187)	(1,172)
Cash flow hedges: Unrealized holding (losses) gains, Tax Effect	318	314
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	(869)	(858)
Cash flow hedges: Net unrealized (losses) gains, Before Tax	(1,187)	(1,172)
Cash flow hedges: Net unrealized (losses) gains, Tax Effect	318	314
Cash flow hedges: Net unrealized (losses) gains, Net of Tax	(869)	(858)
Pension Plan [Member]
Unrealized net actuarial loss, Before Tax	(4,456)	(4,355)
Unrealized net actuarial loss, Tax Effect	1,194	1,166
Unrealized net actuarial loss, Net of Tax	(3,262)	(3,189)
Net plan liability adjustment, Before Tax	(3,023)	(3,278)
Net plan liability adjustment, Tax Effect	810	878
Net plan liability adjustment, Net of Tax	(2,213)	(2,400)
Pension Plan [Member] | Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(1,433)	(1,077)
Less: amortization of unrecognized loss, Tax Effect	384	288
Less: amortization of unrecognized loss, Net of Tax	(1,049)	(789)
SERP [Member]
Unrealized net actuarial loss, Before Tax	(854)	(997)
Unrealized net actuarial loss, Tax Effect	229	267
Unrealized net actuarial loss, Net of Tax	(625)	(730)
Net plan liability adjustment, Before Tax	(666)	(884)
Net plan liability adjustment, Tax Effect	179	237
Net plan liability adjustment, Net of Tax	(487)	(647)
SERP [Member] | Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(188)	(116)
Less: amortization of unrecognized loss, Tax Effect	50	31
Less: amortization of unrecognized loss, Net of Tax	$ (138)	(85)
SERP [Member] | Amortization of Prior Service Costs [Member]
Less: amortization of prior service costs, Before Tax		3
Less: amortization of prior service costs, Tax Effect		(1)
Less: amortization of prior service costs, Net of Tax		$ 2