Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2014
Mar. 05, 2015
Jun. 30, 2014
Document and Entity Information      
Entity Registrant Name TrueCar, Inc.    
Entity Central Index Key 0001327318    
Document Type 10-K    
Document Period End Date Dec. 31, 2014    
Entity Current Reporting Status Yes    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2014    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Filer Category Non-accelerated Filer    
Entity Public Float     $ 391,333,962
Entity Common Stock, Shares Outstanding   80,419,146  
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No