Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	AKBA
Title of 12(b) Security	Common Stock, par value $0.00001 per share
Security Exchange Name	NASDAQ
Entity Registrant Name	AKEBIA THERAPEUTICS, INC.
Entity Central Index Key	0001517022
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		130,265,945
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	245 First Street
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
City Area Code	617
Local Phone Number	871-2098
Entity Address, Postal Zip Code	02142
Entity Tax Identification Number	20-8756903
Entity File Number	001-36352