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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | $ 988 | $ 2,059 | $ (2,557) | $ 8,370
Reclassification adjustment for net (gains) losses included in net income |  | 0 | 0 | 0 | (71)
Tax effect | [1] | (201) | (379) | 541 | (1,772)
Unrealized gains (losses), net of tax |  | 808 | 1,657 | (1,974) | 6,396
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 |  | 988 | 2,059 | (2,557) | 8,370
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 |  |  |  | (2,557) | 8,299
Tax effect |  | (201) | (379) | 541 | (1,772)
Unrealized gains (losses), net of tax |  | 787 | 1,680 | (2,016) | 6,527
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 |  | 36 | 253 | 23 | (140)
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 |  |  |  | 23 | (140)
Tax effect |  | 0 | 0 | 0 | 0
Unrealized gains (losses), net of tax |  | 36 | 253 | 23 | (140)
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 |  | 952 | 1,806 | (2,580) | 8,510
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 |  |  |  | (2,580) | 8,439
Tax effect |  | (201) | (379) | 541 | (1,772)
Unrealized gains (losses), net of tax |  | 751 | 1,427 | (2,039) | 6,667
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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