Credit Arrangements (Details) - USD ($)	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Credit Arrangements [Abstract]
Pledged bonds	$ 8,387,713	$ 8,843,417
Asset Pledged as Collateral [Member]
Credit Arrangements [Abstract]
Pledged bonds	21,716,686
Cash Management Advance [Member]
Credit Arrangements [Abstract]
Borrowings	$ 0
Cash Management Advance [Member] \| Variable Rate [Member] \| Maximum [Member]
Credit Arrangements [Abstract]
Period of interest under CMA	90 days
Cash Management Advance [Member] \| Fixed Rate [Member] \| Maximum [Member]
Credit Arrangements [Abstract]
Period of interest under CMA	30 days

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details