v3.26.1
Segments - Schedule of Revenues by Major Products and Activities (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Product Information [Line Items]        
Revenues $ 4,142 $ 4,176 $ 8,124 $ 8,067
United States [Member]        
Product Information [Line Items]        
Revenues 1,702 1,786 3,236 3,322
Europe [Member]        
Product Information [Line Items]        
Revenues 1,263 1,298 2,603 2,492
International Markets [Member]        
Product Information [Line Items]        
Revenues 550 495 1,074 1,077
Generic products (including OTC and biosimilars) [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 660 961 1,272 1,809
Generic products (including OTC and biosimilars) [Member] | Europe [Member]        
Product Information [Line Items]        
Revenues 1,024 1,040 2,113 2,029
Generic products (including OTC and biosimilars) [Member] | International Markets [Member]        
Product Information [Line Items]        
Revenues 419 410 805 878
AJOVY [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 116 63 203 117
AJOVY [Member] | Europe [Member]        
Product Information [Line Items]        
Revenues 78 71 154 129
AJOVY [Member] | International Markets [Member]        
Product Information [Line Items]        
Revenues 49 20 83 48
AUSTEDO [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 676 495 1,236 891
AUSTEDO [Member] | International Markets [Member]        
Product Information [Line Items]        
Revenues 20 3 39 18
BENDEKA and TREANDA [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 28 40 55 76
COPAXONE [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 61 62 124 116
COPAXONE [Member] | Europe [Member]        
Product Information [Line Items]        
Revenues 49 50 89 92
COPAXONE [Member] | International Markets [Member]        
Product Information [Line Items]        
Revenues 8 7 13 17
UZEDY [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 77 54 140 93
Respiratory Product [Member] | Europe [Member]        
Product Information [Line Items]        
Revenues 58 55 117 110
Other [Member] | United States [Member]        
Product Information [Line Items]        
Revenues 84 111 206 220
Other [Member] | Europe [Member]        
Product Information [Line Items]        
Revenues 54 [1] 81 [1] 130 [2] 132 [2]
Other [Member] | International Markets [Member]        
Product Information [Line Items]        
Revenues $ 55 [1] $ 55 [1] $ 134 [2] $ 116 [2]
[1] Other revenues in the second quarter of 2025 include the sale of certain product rights.
[2] Other revenues in the first six months of 2026 and 2025 include the sale of certain product rights.