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Loans and Allowance for Credit Losses - Narrative (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 USD ($) loan | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) loan | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) loan
Financing Receivable, Past Due [Line Items] |  |  |  |  |
Loans greater than 90 days past due | $ 0 |  | $ 0 |  | $ 0
Number of collateral dependent loans in process of foreclosure | loan | 0 |  | 0 |  | 0
Interest income related to non-accrual loans | $ 0 | $ 0 | $ 0 | $ 0 |
Foregone interest income related to non-accrual loans | 38,200 | $ 26,100 | 77,400 | $ 35,300 |
Pledged loans | 1,600,000,000 |  | 1,600,000,000 |  | $ 1,700,000,000
Federal Reserve Bank of San Francisco |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |
FRB pledged loans | $ 1,200,000,000 |  | $ 1,200,000,000 |  | $ 1,200,000,000

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