XML 11 R1.htm IDEA: XBRL DOCUMENT v3.20.2
Document and Entity Information - shares
 9 Months Ended
Sep. 30, 2020
Nov. 10, 2020
Document and Entity Information    
Document Type 10-Q  
Document Period End Date Sep. 30, 2020  
Entity Registrant Name LEAP THERAPEUTICS, INC.  
Title of 12(b) Security Common Stock, par value $0.001 per share  
Trading Symbol LPTX  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   59,657,742
Entity Central Index Key 0001509745  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q3  
Amendment Flag false