Document and Entity Information - shares
6 Months Ended
Jun. 30, 2019
Jul. 19, 2019
Cover page.    
Entity Interactive Data Current Yes  
Title of 12(b) Security Common Stock, $0.01 par value per share  
Entity Address, Address Line One 11115 Rushmore Drive  
Entity Incorporation, State or Country Code DE  
Entity File Number 001-34063  
Document Quarterly Report true  
Document Transition Report false  
Entity Registrant Name LendingTree, Inc.  
Entity Central Index Key 0001434621  
Document Type 10-Q  
Document Period End Date Jun. 30, 2019  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   12,988,997
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Shell Company false  
Entity Tax Identification Number 26-2414818  
Entity Address, City or Town Charlotte  
Entity Address, State or Province NC  
Entity Address, Postal Zip Code 28277  
City Area Code 704  
Local Phone Number 541-5351  
Trading Symbol TREE  
Security Exchange Name NASDAQ