v3.10.0.1
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2018
Oct. 31, 2018
Entity Registrant Name Liberty TripAdvisor Holdings, Inc.  
Entity Central Index Key 0001606745  
Document Type 10-Q  
Document Period End Date Sep. 30, 2018  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Series A    
Entity Common Stock, Shares Outstanding   72,130,278
Series B    
Entity Common Stock, Shares Outstanding   2,929,777