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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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