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Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount of accumulated undistributed earnings (deficit).

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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2023	Jan. 01, 2023	Dec. 31, 2022
Summary of Significant Accounting Policies
Accrued interest receivable on available-for-sale debt securities	$ 2,500,000
Accrued interest receivable on loans receivable	1,200,000
Amount of loans evaluated for determination of allowance for credit losses	100,000
Retained earnings	42,629,000		$ 41,945,000
Loans	$ 462,730,000		$ 458,823,000
Cumulative effect of adoption of ASU 2016-13 \| ASU No. 2016-13
Summary of Significant Accounting Policies
Retained earnings		$ 2,088,000
Cumulative effect of adoption of ASU 2016-13 \| ASU No. 2016-13 \| Loans other than unfunded loan commitments
Summary of Significant Accounting Policies
Loans		1,911,000
Cumulative effect of adoption of ASU 2016-13 \| ASU No. 2016-13 \| Unfunded loan commitments
Summary of Significant Accounting Policies
Loans		$ 177,000