v3.26.3
DocumentAndEntityInformation
Sep. 23, 2026
Document Information Line Items  
Entity Central Index Key 0000874015
Document Type 8-K
Document Period End Date Sep. 23, 2026
Entity Registrant Name IONIS PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code DE
Entity File Number 000-19125
Entity Tax Identification Number 33-0336973
Entity Address, Address Line One 2855 Gazelle Court
Entity Address, City or Town Carlsbad
Entity Address, State or Province CA
Entity Address, Postal Zip Code 92010
City Area Code 760
Local Phone Number 931-9200
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, $.001 Par Value   “ION   The Nasdaq Stock Market, LLC
Trading Symbol ION
Security Exchange Name NASDAQ
Entity Emerging Growth Company false
Amendment Flag false