Loans and Allowance for Credit Losses - Narrative (Details)	3 Months Ended
Mar. 31, 2024 USD ($) loan	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) loan
Financing Receivable, Past Due [Line Items]
Loans greater than 90 days past due	$ 0		$ 0
Number of collateral dependent loans in process of foreclosure \| loan	0		0
Interest income related to non-accrual loans	$ 39,200	$ 9,100
Pledged loans	1,700,000,000		$ 1,700,000,000
Federal Reserve Bank of San Francisco
Financing Receivable, Past Due [Line Items]
FRB pledged loans	$ 1,200,000,000

Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged

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- Definition

Number Of Collateral Dependent Loans In Process Of Foreclosure

+ References

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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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.

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