v3.26.1
Fair Value of Assets and Liabilities - Schedule of Prosper's and Prosper Funding's Estimated Fair Value of Servicing Assets and Liabilities (Details) - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Servicing Assets And Liabilities Fair Value [Line Items]    
Servicing Assets $ 19,659 $ 17,402
Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Servicing Assets 19,754 17,601
Servicing Assets    
Servicing Assets And Liabilities Fair Value [Line Items]    
Servicing Assets 19,659 17,402
Servicing Assets | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Servicing Assets 19,754 17,601
Market servicing rate | Servicing Assets | Market servicing rate increase of 0.025%    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 18,534 16,398
Servicing rate increase 0.025%  
Market servicing rate | Servicing Assets | Market servicing rate increase of 0.025% | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 18,624 16,586
Servicing rate increase 0.025%  
Market servicing rate | Servicing Assets | Market servicing rate decrease of 0.025%    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 20,784 18,405
Servicing rate decrease 0.025%  
Market servicing rate | Servicing Assets | Market servicing rate decrease of 0.025% | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 20,884 18,615
Servicing rate decrease 0.025%  
Prepayment rate assumption | Servicing Assets | Applying a 1.1 multiplier to prepayment rate    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 19,352 16,949
Prepayment rate increase 1.10%  
Prepayment rate assumption | Servicing Assets | Applying a 1.1 multiplier to prepayment rate | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 19,445 17,143
Prepayment rate assumption | Servicing Assets | Applying a 0.9 multiplier to prepayment rate    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 19,967 17,863
Prepayment rate decrease 0.90%  
Prepayment rate assumption | Servicing Assets | Applying a 0.9 multiplier to prepayment rate | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 20,063 18,068
Default rate assumption | Servicing Assets | Applying a 1.1 multiplier to default rate    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 19,136 17,114
Default rate increase 1.10%  
Default rate assumption | Servicing Assets | Applying a 1.1 multiplier to default rate | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 19,228 17,310
Default rate assumption | Servicing Assets | Applying a 0.9 multiplier to default rate    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 20,195 17,689
Default rate decrease 0.90%  
Default rate assumption | Servicing Assets | Applying a 0.9 multiplier to default rate | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Expected fair value with change in assumptions $ 20,292 $ 17,892
Market servicing rate | Servicing Assets    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 0.598% 0.598%
Market servicing rate | Servicing Assets | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 0.598% 0.598%
Prepayment rate | Applying a 1.1 multiplier to prepayment rate | Credit Card Servicing Obligation Liability    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate increase 110.00%  
Prepayment rate | Applying a 1.1 multiplier to prepayment rate | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate increase 1.10%  
Prepayment rate | Applying a 1.1 multiplier to prepayment rate | Prosper Funding LLC | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate increase 110.00%  
Prepayment rate | Applying a 1.2 multiplier to default rate | Prosper Funding LLC | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate decrease 120.00%  
Prepayment rate | Applying a 0.9 multiplier to prepayment rate | Credit Card Servicing Obligation Liability    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate decrease 90.00%  
Prepayment rate | Applying a 0.9 multiplier to prepayment rate | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate decrease 0.90%  
Prepayment rate | Applying a 0.9 multiplier to prepayment rate | Prosper Funding LLC | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Prepayment rate increase 90.00%  
Prepayment rate | Servicing Assets    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 21.68% 21.65%
Prepayment rate | Servicing Assets | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 21.72% 21.72%
Default rate | Applying a 1.1 multiplier to default rate | Credit Card Servicing Obligation Liability    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate increase 110.00%  
Default rate | Applying a 1.1 multiplier to default rate | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate increase 1.10%  
Default rate | Applying a 1.1 multiplier to default rate | Prosper Funding LLC | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate decrease 110.00%  
Default rate | Applying a 0.9 multiplier to default rate | Credit Card Servicing Obligation Liability    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate decrease 90.00%  
Default rate | Applying a 0.9 multiplier to default rate | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate decrease 0.90%  
Default rate | Applying a 0.9 multiplier to default rate | Prosper Funding LLC | Credit Card Derivative    
Servicing Assets And Liabilities Fair Value [Line Items]    
Default rate decrease 90.00%  
Default rate | Servicing Assets    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 11.16% 11.84%
Default rate | Servicing Assets | Prosper Funding LLC    
Servicing Assets And Liabilities Fair Value [Line Items]    
Valuation techniques 11.17% 11.86%