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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, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | $ (6,708) | $ (22,815) | $ (5,736) | $ (56,413)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 0 | 0 | 67 | 0
Tax effect | [1] | 1,394 | 4,788 | 1,266 | 11,687
Unrealized gains (losses), net of tax |  | (5,314) | (18,027) | (4,537) | (44,726)
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 |  | (6,708) | (22,815) | (5,736) | (56,413)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 0 | 0 | (67) | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | (6,708) | (22,815) | (5,803) | (56,413)
Tax effect |  | 1,394 | 4,788 | 1,266 | 11,687
Unrealized gains (losses), net of tax |  | (5,314) | (18,027) | (4,537) | (44,726)
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 |  | (67) | (18) | 228 | (763)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 0 | 0 | 0 | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | (67) | (18) | 228 | (763)
Tax effect |  | 0 | 0 | 0 | 0
Unrealized gains (losses), net of tax |  | (67) | (18) | 228 | (763)
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 |  | (6,641) | (22,797) | (5,964) | (55,650)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 0 | 0 | (67) | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | (6,641) | (22,797) | (6,031) | (55,650)
Tax effect |  | 1,394 | 4,788 | 1,266 | 11,687
Unrealized gains (losses), net of tax |  | (5,247) | (18,009) | (4,765) | (43,963)
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 9 – Accumulated Other Comprehensive Income” for tax effect reconciliation.

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