Accumulated Other Comprehensive Loss (Components of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	$ (5,202)	$ 1,384
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	405	(963)
Unrealized net actuarial loss, Net of Tax	133	(4,915)
Other Comprehensive Income, Before Tax Amount	(5,943)	(7,692)
Other Comprehensive Income, Tax (Expense) Benefit	1,608	2,060
Other Comprehensive (loss) Income, Net	(4,335)	(5,632)
Investment securities- with OTTI [Member]
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Before Tax Amount	363	(1,623)
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, tax effect	(97)	435
Available for sale (AFS) securities with OTTI: Unrealized holding (losses) gains, Net of Tax	266	(1,188)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Before Tax Amount	50	50
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Tax Effect	(13)	(13)
Available for sale (AFS) securities with OTTI: Less: accretable yield recognized in income, Net of Tax	37	37
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Before Tax Amount	313	(1,673)
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Tax Effect	(84)	448
Available for sale (AFS) securities with OTTI: Net unrealized losses on investments with OTTI, Net of Tax	229	(1,225)
Investment Securities -All Other AFS [Member]
Securities: Unrealized holding gains (losses), Before Tax	(7,105)	1,890
Securities: Unrealized holding gains (losses), Tax Effect	1,903	(506)
Securities: Unrealized holding gains (losses), Net of Tax	(5,202)	1,384
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Before Tax	(7,105)	1,890
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Tax Effect	1,903	(506)
Available for sale securities - all other: Net unrealized losses on all other AFS securities, Net of tax	(5,202)	1,384
Investment Securities HTM [Member]
Held to maturity securities: Net unrealized gains on all HTM securities, Before tax	61	72
Held to maturity securities: Net unrealized gains on all HTM securities, Tax	(16)	(19)
Held to maturity securities: Net unrealized gains on all HTM securities, After tax	45	53
Investment Securities HTM [Member] \| Amortization of Recognized Income [Member]
Less: amortization recognized in income, Before Tax	(61)	(72)
Less: amortization recognized in income, Tax Effect	16	19
Less: amortization recognized in income, Net of Tax	(45)	(53)
Cash Flow Hedge (OCI) [Member]
Cash flow hedges: Unrealized holding (losses) gains, Before Tax	532	(1,315)
Cash flow hedges: Unrealized holding (losses) gains, Tax Effect	(127)	352
Cash flow hedges: Unrealized holding (losses) gains, Net of Tax	405	(963)
Pension Plan [Member]
Unrealized net actuarial loss, Before Tax	(190)	(7,070)
Unrealized net actuarial loss, Tax Effect	51	1,893
Unrealized net actuarial loss, Net of Tax	(139)	(5,177)
Net plan liability adjustment, Before Tax	182	(6,712)
Net plan liability adjustment, Tax Effect	(49)	1,797
Net plan liability adjustment, Net of Tax	133	(4,915)
Pension Plan [Member] \| Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(372)	(358)
Less: amortization of unrecognized loss, Tax Effect	100	96
Less: amortization of unrecognized loss, Net of Tax	(272)	(262)
SERP [Member]
Net plan liability adjustment, Before Tax	74	46
Net plan liability adjustment, Tax Effect	(19)	(12)
Net plan liability adjustment, Net of Tax	55	34
SERP [Member] \| Amortization of Unrecognized Loss [Member]
Less: amortization of unrecognized loss, Before Tax	(75)	(47)
Less: amortization of unrecognized loss, Tax Effect	19	12
Less: amortization of unrecognized loss, Net of Tax	(56)	(35)
SERP [Member] \| Amortization of Prior Service Costs [Member]
Less: amortization of prior service costs, Before Tax	1	1
Less: amortization of prior service costs, Net of Tax	$ 1	$ 1

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Other comprehensive income loss held to maturity securities adjustment before tax.

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