Revenue - Schedule of Disaggregation of Revenue by Type of Service (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Disaggregation of Revenue [Line Items]
Total revenue from fees, net	$ 364,030	$ 258,539	$ 989,112	$ 684,791
Platform and referral fees, net
Disaggregation of Revenue [Line Items]
Total revenue from fees, net	283,139	216,882	791,823	570,702
Servicing and other fees, net
Disaggregation of Revenue [Line Items]
Total revenue from fees, net	69,807	41,657	173,726	114,089
Loan sales fees
Disaggregation of Revenue [Line Items]
Total revenue from fees, net	$ 11,084	$ 0	$ 23,563	$ 0

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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+ Details