v3.25.4
Segment, Geographic and Other Revenue Information - Narrative (Detail)
treatment_course in Millions, $ in Millions
2 Months Ended 3 Months Ended 12 Months Ended
Feb. 29, 2024
treatment_course
Sep. 29, 2024
USD ($)
treatment_course
Mar. 31, 2024
USD ($)
Dec. 31, 2025
USD ($)
segment
country
Dec. 31, 2024
USD ($)
country
Dec. 31, 2023
USD ($)
treatment_course
country
Segment Reporting Information [Line Items]            
Number of operating segments | segment       3    
Number of reportable segments | segment       1    
Total assets       $ 208,160 $ 213,396  
Deferred revenues, current       784 1,511  
Paxlovid, EUA-Labeled [Member]            
Segment Reporting Information [Line Items]            
Reversal of revenue           $ 3,500
Estimated government emergency use authorization inventory to be returned to company, number of treatment courses | treatment_course           6.5
Favorable adjustment for government emergency use authorization inventory returned to the company during the period     $ 771   771  
Government emergency use authorization inventory returned to the company during the period, number of treatment courses | treatment_course 5.1          
Paxlovid, NDA-Labeled, U.S. Strategic National Stockpile [Member]            
Segment Reporting Information [Line Items]            
Supply commitment, minimum amount committed, number of treatment courses | treatment_course   1.0        
Revenues   $ 442        
Comirnaty [Member]            
Segment Reporting Information [Line Items]            
Remaining performance obligation       2,100    
Paxlovid [Member]            
Segment Reporting Information [Line Items]            
Remaining performance obligation       1,000    
Government and Government Sponsored [Member] | Paxlovid and Comirnaty [Member]            
Segment Reporting Information [Line Items]            
Deferred revenues       1,500 2,200  
Deferred revenues, current       689 1,400  
Deferred revenues, noncurrent       826 $ 785  
Deferred revenue, revenue recognized       $ 771    
Geographic Concentration Risk [Member] | Revenue [Member] | Outside United States [Member]            
Segment Reporting Information [Line Items]            
Number of countries with revenue exceeding $500 million | country       12 11 14
Geographic Concentration Risk [Member] | Revenue [Member] | U.S. [Member]            
Segment Reporting Information [Line Items]            
Concentration risk, percentage       10.00% 10.00% 10.00%
Geographic Concentration Risk [Member] | Revenue [Member] | China [Member]            
Segment Reporting Information [Line Items]            
Concentration risk, percentage       5.00% 4.00%  
Geographic Concentration Risk [Member] | Revenue [Member] | Japan [Member]            
Segment Reporting Information [Line Items]            
Concentration risk, percentage           6.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Three Largest U.S. Wholesaler Customers [Member]            
Segment Reporting Information [Line Items]            
Concentration risk, percentage       40.00% 34.00%