Document and Entity Information
Jul. 23, 2019
Document and Entity Information [Abstract]  
Document Type 8-K
Document Period End Date Jul. 23, 2019
Amendment Flag false
Entity Registrant Name SEATTLE GENETICS INC /WA
Entity Central Index Key 0001060736
Title of 12(b) Security Common Stock, par value $0.001
Trading Symbol SGEN
Security Exchange Name NASDAQ
Entity File Number 0-32405
Entity Incorporation, State or Country Code DE
Entity Tax Identification Number 91-1874389
Entity Address, Address Line One 21823 30th Drive SE
Entity Address, City or Town Bothell
Entity Address, State or Province WA
Entity Address, Postal Zip Code 98021
City Area Code 425
Local Phone Number 527-4000
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false