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Investment Securities - Pledged and Transferred Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | $ 220,292 | $ 217,849
Public deposits |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | 217,143 | 213,861
Trust deposits |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | 676 | 729
Internal checking account |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | 568 | 614
State of California |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | 218,387 | 215,204
Bankruptcy trustee deposits |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Available-for-sale securities pledged as collateral | $ 1,905 | $ 2,645

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Fair value of the securities pledged as collateral against securities loaned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313 + Details
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