Document and Entity Information Document and Entity Information
Jun. 01, 2021
May 12, 2021
Document and Entity Information [Abstract]    
Document Type 8-K  
Document Period End Date Jun. 01, 2021  
Entity Registrant Name Phillips 66  
Entity Incorporation, State or Country Code DE  
Entity File Number 001-35349  
Entity Tax Identification Number 45-3779385  
Entity Address, Address Line One 2331 CityWest Boulevard  
Entity Address, City or Town Houston  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 77042  
City Area Code 281  
Local Phone Number 293-6600  
Written Communications false  
Soliciting Material false  
Pre-commencement Tender Offer false  
Pre-commencement Issuer Tender Offer false  
Title of 12(b) Security Common stock, $0.01 par value  
Trading Symbol PSX  
Security Exchange Name NYSE  
Entity Emerging Growth Company false  
Entity Central Index Key   0001534701
Amendment Flag   false