v3.26.1
Cover Page - USD ($)
 12 Months Ended
Dec. 31, 2025
Mar. 24, 2026
Jun. 30, 2025
Entity Information [Line Items]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity Registrant Name PROSPER MARKETPLACE, INC.    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 73-1733867    
Entity File Number 333-257739    
Entity Address, Address Line One 221 Main Street    
Entity Address, Address Line Two 3rd Floor    
Entity Address, City or Town San Francisco    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94105    
City Area Code 415    
Local Phone Number 593-5426    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction Flag false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   78,299,355  
Entity Public Float     $ 0
Document Fiscal Year Focus 2025    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Central Index Key 0001416265    
Prosper Funding LLC      
Entity Information [Line Items]      
Current Fiscal Year End Date --12-31    
Entity Registrant Name PROSPER FUNDING LLC    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 45-4526070    
Entity File Number 333-257739-01    
Entity Address, Address Line One 221 Main Street    
Entity Address, Address Line Two 3rd Floor    
Entity Address, City or Town San Francisco    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94105    
City Area Code 415    
Local Phone Number 593-5426    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction Flag false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   0  
Entity Central Index Key 0001542574