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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | $ (66) | $ 1,724 | $ 8,304 | $ 12,554
Reclassification adjustment for net (gains) losses included in net income |  | 0 | (6) | (71) | (6)
Tax effect | [1] | 58 | (310) | (1,714) | (2,523)
Unrealized gains (losses), net of tax |  | 8 | 1,379 | 6,404 | 9,831
Unrealized Holding Gains (Losses) on AFS Securities [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | (66) | 1,724 | 8,304 | 12,554
Reclassification adjustment for net (gains) losses included in net income |  | 0 | (6) | (71) | (6)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  | (66) | 1,718 | 8,233 | 12,548
Tax effect |  | 58 | (310) | (1,714) | (2,523)
Unrealized gains (losses), net of tax |  | (8) | 1,408 | 6,519 | 10,025
Unrealized Holding Gains (Losses) on AFS Securities [Member] | Auction Rate Money Market Preferred and Preferred Stocks [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | 215 | 240 | 75 | 535
Reclassification adjustment for net (gains) losses included in net income |  | 0 | 0 | 0 | 0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  | 215 | 240 | 75 | 535
Tax effect |  | 0 | 0 | 0 | 0
Unrealized gains (losses), net of tax |  | 215 | 240 | 75 | 535
Unrealized Holding Gains (Losses) on AFS Securities [Member] | All Other AFS Securities [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | (281) | 1,484 | 8,229 | 12,019
Reclassification adjustment for net (gains) losses included in net income |  | 0 | (6) | (71) | (6)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  | (281) | 1,478 | 8,158 | 12,013
Tax effect |  | 58 | (310) | (1,714) | (2,523)
Unrealized gains (losses), net of tax |  | (223) | 1,168 | 6,444 | 9,490
Accumulated Defined Benefit Plans Adjustment [Member] |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses), net of tax |  | $ 0 | $ 0 | $ 0 | $ 0
[1] | See “Note 10 – Accumulated Other Comprehensive Income” for tax effect reconciliation.

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- Definition Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580 + Details
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