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Accumulated Other Comprehensive Income (Loss) (Components of unrealized holding gains on AFS securities) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Unrealized gains (losses) on AFS securities arising during the period |  | $ 8,610 | $ (22,928)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 1 | 0
Tax effect | [1] | (1,729) | 4,736
Unrealized gains (losses), net of tax |  | 6,880 | (18,192)
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 |  | 8,610 | (22,928)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | (1) | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | 8,609 | (22,928)
Tax effect |  | (1,729) | 4,736
Unrealized gains (losses), net of tax |  | 6,880 | (18,192)
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 |  | 374 | (375)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | 0 | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | 374 | (375)
Tax effect |  | 0 | 0
Unrealized gains (losses), net of tax |  | 374 | (375)
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 |  | 8,236 | (22,553)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax |  | (1) | 0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax |  | 8,235 | (22,553)
Tax effect |  | (1,729) | 4,736
Unrealized gains (losses), net of tax |  | 6,506 | (17,817)
Accumulated Defined Benefit Plans Adjustment [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Unrealized gains (losses), net of tax |  | $ 0 | $ 0
[1] | See “Note 9 – Accumulated Other Comprehensive Income” for tax effect reconciliation.

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- Definition Amount, before tax and after adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. + 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 (f) -URI https://asc.fasb.org/extlink&oid=126968391&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 (e) -URI https://asc.fasb.org/extlink&oid=126968391&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 11 -URI https://asc.fasb.org/extlink&oid=126968391&loc=d3e637-108580 + Details
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- Definition Amount, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. + 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 https://asc.fasb.org/extlink&oid=126968391&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 https://asc.fasb.org/extlink&oid=126968391&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 https://asc.fasb.org/extlink&oid=126968391&loc=d3e640-108580 + Details
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