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Junior and Other Subordinated Debentures (Narrative) (Details) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Feb. 28, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Junior Subordinated Debentures [Line Items] |  |  |  |
Junior and other subordinated debentures, at amortized cost |  | $ 107,895 | $ 87,813 |
Common stock issued by Trusts |  | 14,300 | 14,000 |
Unrealized gains (losses) arising during the period |  | 7,866 | $ (28,842) | $ (37,899)
Other Subordinated Debt |  |  |  |
Junior Subordinated Debentures [Line Items] |  |  |  |
Junior and other subordinated debentures, at amortized cost | $ 10,000 |  |  |
Basis spread on SOFR+0.26161% | 5.26% |  |  |
Junior Subordinated Debt, at Amortized Cost |  |  |  |
Junior Subordinated Debentures [Line Items] |  |  |  |
Junior and other subordinated debentures, at amortized cost |  | 97,895 |  |
Junior Subordinated Debt, at Amortized Cost | Bank of Commerce Holdings Trust II |  |  |  |
Junior Subordinated Debentures [Line Items] |  |  |  |
Junior and other subordinated debentures, at amortized cost | $ 10,300 | $ 10,310 |  |
Basis spread on SOFR+0.26161% |  | 1.58% |  |

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- Definition Amount, before tax and reclassification adjustment, of unrealized gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482736/825-10-45-5 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 30 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-30 + Details
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