v3.19.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2019
Aug. 07, 2019
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Trading Symbol LIFE  
Entity Registrant Name aTYR PHARMA INC  
Entity Central Index Key 0001339970  
Entity Current Reporting Status Yes  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Entity Shell Company false  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period true  
Entity Common Stock, Shares Outstanding   3,890,185
Entity File Number 001-37378  
Entity Tax Identification Number 203435077  
Entity Address, Address Line One 3545 John Hopkins Court  
Entity Address, Address Line Two Suite #250  
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 731-8389