Fair Value Measurement - Carrying amounts and fair value (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Carrying Amount \| Level 1
Fair Value Measurement
Cash and cash equivalents	$ 11,172	$ 18,066
Notes payable (listed) – fixed rate debt	173,254	230,239
Investment securities	1,429	1,517
Carrying Amount \| Level 2
Fair Value Measurement
Lines of credit and repurchase agreements – variable rate debt	40,565	73,708
Carrying Amount \| Level 3
Fair Value Measurement
Loans held for investment, net	361,740	356,571
Loans held for sale, net	8,797	10,970
Interest and fees receivable and due from borrowers	9,859	8,918
Investments in limited liability companies	41,167	53,942
Advances from borrowers	5,811	4,047
Senior secured notes payable	90,000	0
Mortgage payable	939	1,002
Fair Value Measurement \| Level 1
Fair Value Measurement
Cash and cash equivalents	11,172	18,066
Notes payable (listed) – fixed rate debt	162,449	194,810
Investment securities	1,429	1,517
Fair Value Measurement \| Level 2
Fair Value Measurement
Lines of credit and repurchase agreements – variable rate debt	40,565	73,708
Fair Value Measurement \| Level 3
Fair Value Measurement
Loans held for investment, net	361,740	356,571
Loans held for sale, net	8,797	10,970
Interest and fees receivable and due from borrowers	9,859	8,918
Investments in limited liability companies	41,167	53,942
Advances from borrowers	5,811	4,047
Senior secured notes payable	91,038	0
Mortgage payable	$ 939	$ 1,002

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Mortgage Payable, Fair Value Disclosure

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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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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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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value portion of notes payable.

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