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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | $ (1,690) | $ (66) | $ (4,247) | $ 8,304
Reclassification adjustment for net (gains) losses included in net income |  | 0 | 0 | 0 | (71)
Tax effect | [1] | 353 | 58 | 894 | (1,714)
Unrealized gains (losses), net of tax |  | (1,337) | 8 | (3,311) | 6,404
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 |  | (1,690) | (66) | (4,247) | 8,304
Reclassification adjustment for net (gains) losses included in net income |  |  |  | 0 | (71)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  |  |  | (4,247) | 8,233
Tax effect |  | 353 | 58 | 894 | (1,714)
Unrealized gains (losses), net of tax |  | (1,337) | (8) | (3,353) | 6,519
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 |  | (14) | 215 | 9 | 75
Reclassification adjustment for net (gains) losses included in net income |  |  |  | 0 | 0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  |  |  | 9 | 75
Tax effect |  | 0 | 0 | 0 | 0
Unrealized gains (losses), net of tax |  | (14) | 215 | 9 | 75
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 |  | (1,676) | (281) | (4,256) | 8,229
Reclassification adjustment for net (gains) losses included in net income |  |  |  | 0 | (71)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, Portion Attributable to Parent |  |  |  | (4,256) | 8,158
Tax effect |  | 353 | 58 | 894 | (1,714)
Unrealized gains (losses), net of tax |  | (1,323) | (223) | (3,362) | 6,444
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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