v3.26.1
Document and Entity Information - shares
 3 Months Ended
Mar. 31, 2026
May 01, 2026
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2026  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q1  
Trading Symbol IDYA  
Entity Registrant Name IDEAYA Biosciences, Inc.  
Entity Central Index Key 0001676725  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Shell Company false  
Entity Emerging Growth Company false  
Entity Common Stock, Shares Outstanding   87,860,920
Title of 12(b) Security Common Stock, $0.0001 par value per share  
Security Exchange Name NASDAQ  
Entity File Number 001-38915  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 47-4268251  
Entity Address, Address Line One 5000 Shoreline Court  
Entity Address, Address Line Two Suite 300  
Entity Address, City or Town South San Francisco  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 94080  
City Area Code 650  
Local Phone Number 443-6209  
Document Quarterly Report true  
Document Transition Report false