Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Commitments and Contingencies - Narrative (Details) - USD ($)	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Line of Credit Facility [Line Items]
Allowance for credit losses on unfunded commitments	$ 423,000	$ 493,000	$ 464,000	$ 140,000	$ 148,000	$ 139,000
Borrower In Custody Program
Line of Credit Facility [Line Items]
Maximum borrowing capacity	217,900,000		198,800,000
Loans \| Asset Pledged as Collateral \| Federal Reserve Bank Advances
Line of Credit Facility [Line Items]
Total loans held-for-investment, gross	296,200,000		240,800,000
Other unused commitments \| Asset Pledged as Collateral \| Federal Reserve Bank Advances
Line of Credit Facility [Line Items]
Total loans held-for-investment, gross	41,200,000		42,600,000
Line of Credit
Line of Credit Facility [Line Items]
Long-term line of credit	0		0
Line of Credit \| Federal Home Loan Bank Secured Line of Credit
Line of Credit Facility [Line Items]
Available line of credit with the FHLB	24,900,000		25,000,000.0
Amounts outstanding under the FHLB line of credit	0		0
Loans pledged to secure FHLB line of credit	41,500,000		41,600,000
Line of Credit \| Federal Reserve Bank, Discount Window
Line of Credit Facility [Line Items]
Maximum borrowing capacity	257,600,000		239,200,000
Line of Credit \| Zions Bank
Line of Credit Facility [Line Items]
Maximum borrowing capacity	5,000,000.0		5,000,000.0
Line of Credit \| Bank of the West
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 1,100,000		$ 1,100,000