v3.20.4
Cover Page - USD ($)
$ in Billions
12 Months Ended
Dec. 31, 2020
Feb. 23, 2021
Jun. 28, 2020
Entity Information [Line Items]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2020    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 1-3619    
Entity Registrant Name PFIZER INC    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 13-5315170    
Entity Address, Address Line One 235 East 42nd Street    
Entity Address, City or Town New York    
Entity Address, State or Province NY    
Entity Address, Postal Zip Code 10017    
City Area Code 212    
Local Phone Number 733-2323    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
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    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 169
Entity Common Stock, Shares Outstanding   5,577,629,491  
Entity Central Index Key 0000078003    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Amendment Flag false    
Documents Incorporated by Reference
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the Proxy Statement for the 2021 Annual Meeting of ShareholdersPart III
   
Common Stock [Member]      
Entity Information [Line Items]      
Title of 12(b) Security Common Stock, $.05 par value    
Trading Symbol PFE    
Security Exchange Name NYSE    
Notes Due 2022, 0.250% [Member]      
Entity Information [Line Items]      
Title of 12(b) Security 0.250% Notes due 2022    
Trading Symbol PFE22    
Security Exchange Name NYSE    
Notes Due 2027, 1.000% [Member]      
Entity Information [Line Items]      
Title of 12(b) Security 1.000% Notes due 2027    
Trading Symbol PFE27    
Security Exchange Name NYSE