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Investment Securities - Schedule of Financial Instruments Owned and Pledged as Collateral (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | $ 911,559 | $ 941,122
Total investment securities pledged to the State of California |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 302,930 | 290,564
Secure public deposits in compliance with the Local Agency Security Program |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 300,703 | 288,385
Collateral for trust deposits |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 923 | 1,284
Collateral for Wealth Management and Trust Services checking account |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 1,304 | 895
Bankruptcy trustee deposits pledged with Federal Reserve Bank |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 522 | 651
Pledged to FHLB Securities-Backed Credit Program |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | 280,652 | 284,148
Pledged to the Federal Reserve Discount Window |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Total pledged investment securities | $ 327,455 | $ 365,759

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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 -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-12 + Details
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