XML 13 R1.htm IDEA: XBRL DOCUMENT v3.21.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2021
Aug. 10, 2021
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2021  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q2  
Entity Registrant Name COMPASS THERAPEUTICS, INC.  
Entity Central Index Key 0001738021  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Common Stock, Shares Outstanding   61,694,565
Entity Shell Company false  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity File Number 001-39696  
Entity Tax Identification Number 82-4876496  
Entity Address, Address Line One 80 Guest St.  
Entity Address, Address Line Two Suite 601  
Entity Address, City or Town Boston  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02135  
City Area Code 617  
Local Phone Number 500-8099  
Entity Incorporation, State or Country Code DE  
Document Quarterly Report true  
Document Transition Report false  
Title of each class Common Stock, $0.0001 par value per share  
Trading Symbol CMPX