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Threshold period when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of cash inflow from recovery of financing receivable, previously written off.

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Revenue - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Revenue - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Disaggregation of Revenue [Line Items]
Trailing fee liabilities	$ 6,800		$ 6,800		$ 5,800
Receivables	$ 53,379		$ 53,379		46,647
Loans on non-accrual status	120 days		120 days
Accrued interest income	$ 10,700		$ 10,700		10,200
Dividend income	0		11,700
Proceeds from charged-off loans	0	$ 0	25,100	$ 13,000
Convertible senior notes
Disaggregation of Revenue [Line Items]
Interest expense	$ 0		$ 15,200
HELOCs
Disaggregation of Revenue [Line Items]
Loans on non-accrual status	180 days		180 days
Minimum
Disaggregation of Revenue [Line Items]
Subscription agreements term			1 month
Maximum
Disaggregation of Revenue [Line Items]
Subscription agreements term			6 months
Platform and referral fees, net
Disaggregation of Revenue [Line Items]
Loan premium and loan trailing fees recognized	$ 0	0	$ 17,400	12,900
Receivables	$ 25,300		$ 25,300		$ 25,800
Capitalized cost amortization term	3 years		3 years
Origination fees
Disaggregation of Revenue [Line Items]
Origination fees	$ 0	$ 0	$ 14,500	$ 0