Securities - Additional Information (Details)	9 Months Ended
Sep. 30, 2025 USD ($) item	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Securities
Allowance for credit losses	$ 0		$ 0
Carrying value of securities pledged	125,200,000		121,400,000
Fair value of investment in debt securities	$ 198,000,000		$ 208,800,000
Percentage of fair value of investment in debt	78.00%		87.00%
Number of investments in available for sale securities \| item	206
Realized gains (losses) on sale of available-for-sale securities	$ 144,000	$ (116,000)
Proceeds from sale of available-for-sale securities	7,734,000	27,431,000
Tranche One
Securities
Proceeds from sale of available-for-sale securities	140,000,000	20,300,000
Loss on the sale of available-for-sale securities	2,000,000	228,000
Tranche Two
Securities
Proceeds from sale of available-for-sale securities	7,700,000	7,200,000
Gain on sale of available-for-sale securities	$ 145,000	$ 112,000

The percentage of total investment portfolio fair value.

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Schedule Of Marketable Securities [Line Items]

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Amount excluding accrued interest, of allowance for credit loss 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 of realized gain 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 of realized gain (loss) 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 of realized loss 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 of restricted 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount of cash inflow from sale of 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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