v3.26.1
Cover - shares
 6 Months Ended
Jun. 30, 2026
Jul. 30, 2026
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 001-36485  
Entity Registrant Name ARDELYX, INC.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 26-1303944  
Entity Address, Address Line One 400 Fifth Avenue  
Entity Address, Address Line Two Suite 210  
Entity Address, City or Town Waltham  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02451  
City Area Code 617  
Local Phone Number 675-2739  
Title of 12(b) Security Common Stock, par value $0.0001 per share  
Trading Symbol ARDX  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   249,187,572
Entity Central Index Key 0001437402  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Amendment Flag false