Disclosures about Fair Value of Financial Instruments and Other Assets and Liabilities - Collateral Dependent (Details)	Dec. 31, 2025 USD ($) loan	Dec. 31, 2024 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Securities held as collateral at fair value	$ 2,149,000
Loans, net of allowance	$ 487,298,000	$ 486,945,000
Collateral dependent loan \| loan	1
Carrying value	$ 1,130,000
Valuation allowance	457,000
Real Estate
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Loans, net of allowance	$ 1,385,000
Number of loans \| loan	3
Revenue from business assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Loans, net of allowance	$ 312,000
Number of loans \| loan	3
Residential
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Loans, net of allowance	$ 452,000
Number of loans \| loan	2

Number of loans secured on financing receivable.

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Number of loans secured on financing receivable required valuation allowance.

+ References

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- Definition

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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- Definition

Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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- Definition

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

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Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

+ References

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- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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