v3.25.2
Cover - shares
6 Months Ended
Jun. 30, 2025
Aug. 01, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-38419  
Entity Registrant Name Arcus Biosciences, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 47-3898435  
Entity Address, Address Line One 3928 Point Eden Way  
Entity Address, City or Town Hayward  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 94545  
City Area Code 510  
Local Phone Number 694-6200  
Title of 12(b) Security Common Stock, Par Value $0.0001 Per Share  
Trading Symbol RCUS  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   106,430,976
Entity Central Index Key 0001724521  
Current Fiscal Year End Date --12-31  
Amendment Flag false  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2