Document and Entity Information - shares
9 Months Ended
Sep. 30, 2019
Oct. 31, 2019
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 30, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Trading Symbol CRNX  
Entity Registrant Name Crinetics Pharmaceuticals, Inc.  
Entity Central Index Key 0001658247  
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 true  
Entity Current Reporting Status Yes  
Entity Shell Company false  
Entity File Number 001-38583  
Entity Tax Identification Number 26-3744114  
Entity Interactive Data Current Yes  
Document Transition Report false  
Title of 12(b) Security Common Stock, par value $0.001 per share  
Security Exchange Name NASDAQ  
Entity Incorporation, State or Country Code DE  
Document Quarterly Report true  
Entity Address, Address Line One 10222 Barnes Canyon Road  
Entity Address, Address Line Two Bldg. #2  
Entity Address, City or Town San Diego  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 92121  
City Area Code 858  
Local Phone Number 450-6464  
Entity Common Stock, Shares Outstanding   24,222,296