Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 01, 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	AGLE
Entity Registrant Name	AEGLEA BIOTHERAPEUTICS, INC.
Entity Central Index Key	0001636282
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity File Number	001-37722
Entity Tax Identification Number	464312787
Entity Address, Address Line One	901 S. MoPac Expressway
Entity Address, Address Line Two	Barton Oaks Plaza One
Entity Address, Address Line Three	Suite 250
Entity Address, City or Town	Austin
Entity Address, Postal Zip Code	78746
City Area Code	512
Local Phone Number	942-2935
Entity Address, State or Province	TX
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Current Reporting Status	Yes
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		28,885,469