Loans and Allowance for Credit Losses on Loans - Additional Information (Details)	12 Months Ended
Dec. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($)
Financing Receivable, Modified [Line Items]
Interest income	$ 38,000	$ 107,000
Collateral dependent loans	$ 313,000	701,000
Number of loans for which multiple concessions are provided \| loan	1
Payment default for loans modified	$ 0	0
Commercial \| Commercial \| Term Extension
Financing Receivable, Modified [Line Items]
Payment delay	$ 4,000	$ 12,000
Class of financing receivables (as percent)	0.01%	0.01%
Weighted average term extension (in months)	11 months	12 months
Business Assets
Financing Receivable, Modified [Line Items]
Collateral dependent loans	$ 270,000
Uncollateralized
Financing Receivable, Modified [Line Items]
Collateral dependent loans	43,000
Loan Classified as Loss
Financing Receivable, Modified [Line Items]
Loans, net	$ 0	$ 0

The values of collateral dependent loans.

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Amount, after allowance for credit loss, of accrued interest on financing receivable.

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Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

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Amortized cost excluding accrued interest, of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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