Stock-Based Compensation - Schedule of Stock Based Compensation Included in Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 331	$ 349	$ 795	$ 676
Income Statement Location [Axis]: us-gaap:GeneralAndAdministrativeExpense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	266	304	613	586
Income Statement Location [Axis]: us-gaap:SellingAndMarketingExpense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	18	18	33	35
Income Statement Location [Axis]: prosper:OriginationAndServicing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 47	$ 27	$ 149	$ 55

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