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Segment Reporting - Sales of Company's Products (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Segment Reporting Information [Line Items] |  |  |
Sales | $ 64,168 | $ 60,115 | $ 59,283
Increase (decrease) in revenue hedging activities | 195 | 244 | 810
Revenue related to the sale of the marketing rights | 106 | 118 | 165
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 63,277 | 59,208 | 57,555
Operating Segments | Pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 57,400 | 53,583 | 52,005
Operating Segments | Pharmaceutical | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 29,482 | 25,011 | 20,937
Operating Segments | Pharmaceutical | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,311 | 1,199 | 1,116
Operating Segments | Pharmaceutical | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,010 | 960 | 876
Operating Segments | Pharmaceutical | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 509 | 218 | 123
Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 371 | 212 | 166
Operating Segments | Pharmaceutical | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 8,583 | 8,886 | 6,897
Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,485 | 2,368 | 2,241
Operating Segments | Pharmaceutical | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 808 | 665 | 170
Operating Segments | Pharmaceutical | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 711 | 769 | 783
Operating Segments | Pharmaceutical | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 263 | 412 | 602
Operating Segments | Pharmaceutical | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,764 | 1,842 | 1,685
Operating Segments | Pharmaceutical | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 785 | 605 | 428
Operating Segments | Pharmaceutical | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 340 | 302 | 263
Operating Segments | Pharmaceutical | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 252 | 218 | 169
Operating Segments | Pharmaceutical | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 177 | 213 | 238
Operating Segments | Pharmaceutical | Winrevair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 419 | 0 | 0
Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 415 | 367 | 341
Operating Segments | Pharmaceutical | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 287 | 255 | 238
Operating Segments | Pharmaceutical | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 964 | 1,428 | 5,684
Operating Segments | Pharmaceutical | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 394 | 483 | 633
Operating Segments | Pharmaceutical | Delstrigo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 249 | 201 | 151
Operating Segments | Pharmaceutical | Pifeltro |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 163 | 142 | 118
Operating Segments | Pharmaceutical | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 222 | 231 | 258
Operating Segments | Pharmaceutical | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 543 | 710 | 706
Operating Segments | Pharmaceutical | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 114 | 187 | 207
Operating Segments | Pharmaceutical | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,334 | 2,189 | 2,813
Operating Segments | Pharmaceutical | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 935 | 1,177 | 1,700
Operating Segments | Pharmaceutical | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,510 | 2,333 | 2,462
Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 5,877 | 5,625 | 5,550
Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,462 | 3,337 | 3,300
Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,415 | 2,288 | 2,250
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 891 | 907 | 1,728
United States |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 32,277 | 28,480 | 27,206
United States | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 32,151 | 28,343 | 26,811
United States | Operating Segments | Pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 30,290 | 26,539 | 24,989
United States | Operating Segments | Pharmaceutical | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 17,872 | 15,114 | 12,686
United States | Operating Segments | Pharmaceutical | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 626 | 607 | 584
United States | Operating Segments | Pharmaceutical | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 705 | 657 | 579
United States | Operating Segments | Pharmaceutical | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 466 | 209 | 123
United States | Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 303 | 168 | 123
United States | Operating Segments | Pharmaceutical | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,425 | 2,083 | 2,065
United States | Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,919 | 1,837 | 1,724
United States | Operating Segments | Pharmaceutical | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 461 | 561 | 163
United States | Operating Segments | Pharmaceutical | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 472 | 493 | 508
United States | Operating Segments | Pharmaceutical | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 56 | 127 | 346
United States | Operating Segments | Pharmaceutical | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,401 | 1,156 | 922
United States | Operating Segments | Pharmaceutical | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 371 | 264 | 188
United States | Operating Segments | Pharmaceutical | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 303 | 274 | 241
United States | Operating Segments | Pharmaceutical | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 146 | 119 | 89
United States | Operating Segments | Pharmaceutical | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 7 | 32 | 51
United States | Operating Segments | Pharmaceutical | Winrevair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 408 | 0 | 0
United States | Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 388 | 350 | 329
United States | Operating Segments | Pharmaceutical | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 176 | 10 | 1,523
United States | Operating Segments | Pharmaceutical | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 185 | 215 | 274
United States | Operating Segments | Pharmaceutical | Delstrigo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 56 | 49 | 39
United States | Operating Segments | Pharmaceutical | Pifeltro |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 113 | 101 | 87
United States | Operating Segments | Pharmaceutical | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 72 | 81 | 79
United States | Operating Segments | Pharmaceutical | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 469 | 1,151 | 1,248
United States | Operating Segments | Pharmaceutical | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 161 | 223 | 355
United States | Operating Segments | Pharmaceutical | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 729 | 658 | 663
United States | Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,861 | 1,804 | 1,822
United States | Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 732 | 700 | 710
United States | Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,129 | 1,104 | 1,112
United States | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 126 | 137 | 395
Int’l |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 31,891 | 31,635 | 32,077
Int’l | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 31,126 | 30,865 | 30,744
Int’l | Operating Segments | Pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 27,110 | 27,044 | 27,016
Int’l | Operating Segments | Pharmaceutical | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 11,610 | 9,897 | 8,251
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 685 | 592 | 532
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 305 | 303 | 297
Int’l | Operating Segments | Pharmaceutical | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 43 | 10 | 0
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Reblozyl |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 68 | 43 | 43
Int’l | Operating Segments | Pharmaceutical | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 6,158 | 6,803 | 4,832
Int’l | Operating Segments | Pharmaceutical | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 566 | 531 | 518
Int’l | Operating Segments | Pharmaceutical | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 347 | 103 | 7
Int’l | Operating Segments | Pharmaceutical | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 239 | 276 | 275
Int’l | Operating Segments | Pharmaceutical | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 207 | 285 | 256
Int’l | Operating Segments | Pharmaceutical | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 363 | 686 | 762
Int’l | Operating Segments | Pharmaceutical | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 414 | 341 | 240
Int’l | Operating Segments | Pharmaceutical | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 37 | 28 | 22
Int’l | Operating Segments | Pharmaceutical | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 106 | 100 | 79
Int’l | Operating Segments | Pharmaceutical | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 170 | 181 | 187
Int’l | Operating Segments | Pharmaceutical | Winrevair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 11 | 0 | 0
Int’l | Operating Segments | Pharmaceutical | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 27 | 16 | 12
Int’l | Operating Segments | Pharmaceutical | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 287 | 255 | 238
Int’l | Operating Segments | Pharmaceutical | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 787 | 1,418 | 4,161
Int’l | Operating Segments | Pharmaceutical | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 209 | 268 | 359
Int’l | Operating Segments | Pharmaceutical | Delstrigo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 193 | 152 | 111
Int’l | Operating Segments | Pharmaceutical | Pifeltro |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 50 | 41 | 30
Int’l | Operating Segments | Pharmaceutical | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 150 | 150 | 179
Int’l | Operating Segments | Pharmaceutical | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 543 | 710 | 706
Int’l | Operating Segments | Pharmaceutical | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 114 | 187 | 207
Int’l | Operating Segments | Pharmaceutical | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 865 | 1,039 | 1,565
Int’l | Operating Segments | Pharmaceutical | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 774 | 954 | 1,344
Int’l | Operating Segments | Pharmaceutical | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,782 | 1,675 | 1,803
Int’l | Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 4,016 | 3,821 | 3,728
Int’l | Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,729 | 2,637 | 2,590
Int’l | Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,287 | 1,184 | 1,138
Int’l | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | $ 765 | $ 770 | $ 1,333

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