Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Aug. 08, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Trading Symbol	ACHV
Entity Registrant Name	ACHIEVE LIFE SCIENCES, INC.
Entity Central Index Key	0000949858
Current Fiscal Year End Date	--12-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		4,551,005