Document and Entity Information
3 Months Ended
Mar. 31, 2015
May 05, 2015
Document and Entity Information    
Entity Registrant Name 2U, Inc.  
Entity Central Index Key 0001459417  
Document Type 10-Q  
Document Period End Date Mar. 31, 2015  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   41,335,538
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q1