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Segment Reporting - Sales of Company's Products (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Segment Reporting Information [Line Items] |  |  |
Sales | $ 60,115 | $ 59,283 | $ 48,704
Increase (decrease) in revenue hedging activities | 244 | 810 | (203)
Revenue related to the sale of the marketing rights | 118 | 165 | 218
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 59,208 | 57,555 | 48,322
Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 53,583 | 52,005 | 42,754
Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 25,011 | 20,937 | 17,186
Operating Segments | Pharmaceutical segment | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,199 | 1,116 | 989
Operating Segments | Pharmaceutical segment | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 960 | 876 | 704
Operating Segments | Pharmaceutical segment | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 218 | 123 | 13
Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 8,886 | 6,897 | 5,673
Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,368 | 2,241 | 2,135
Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 769 | 783 | 807
Operating Segments | Pharmaceutical segment | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 665 | 170 | 3
Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 412 | 602 | 893
Operating Segments | Pharmaceutical segment | Vaqta |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 180 | 173 | 179
Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,842 | 1,685 | 1,532
Operating Segments | Pharmaceutical segment | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 605 | 428 | 370
Operating Segments | Pharmaceutical segment | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 302 | 263 | 175
Operating Segments | Pharmaceutical segment | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 218 | 169 | (1)
Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 213 | 238 | 259
Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 213 | 239 | 259
Operating Segments | Pharmaceutical segment | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 367 | 341 | 342
Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 255 | 238 | 252
Operating Segments | Pharmaceutical segment | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,428 | 5,684 | 952
Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 483 | 633 | 769
Operating Segments | Pharmaceutical segment | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 231 | 258 | 318
Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 710 | 706 | 825
Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 187 | 207 | 299
Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,189 | 2,813 | 3,324
Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,177 | 1,700 | 1,964
Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,283 | 2,319 | 2,516
Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 5,625 | 5,550 | 5,568
Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,337 | 3,300 | 3,295
Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,288 | 2,250 | 2,273
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 907 | 1,728 | 382
United States |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 28,480 | 27,206 | 22,425
United States | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 28,343 | 26,811 | 22,159
United States | Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 26,539 | 24,989 | 20,401
United States | Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 15,114 | 12,686 | 9,765
United States | Operating Segments | Pharmaceutical segment | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 607 | 584 | 515
United States | Operating Segments | Pharmaceutical segment | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 657 | 579 | 417
United States | Operating Segments | Pharmaceutical segment | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 209 | 123 | 13
United States | Operating Segments | Pharmaceutical segment | Alliance revenue - Reblozyl |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 168 | 123 | 0
United States | Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,083 | 2,065 | 1,881
United States | Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,837 | 1,724 | 1,629
United States | Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 493 | 508 | 473
United States | Operating Segments | Pharmaceutical segment | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 561 | 163 | 3
United States | Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 127 | 346 | 547
United States | Operating Segments | Pharmaceutical segment | Vaqta |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 119 | 95 | 100
United States | Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,156 | 922 | 762
United States | Operating Segments | Pharmaceutical segment | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 264 | 188 | 153
United States | Operating Segments | Pharmaceutical segment | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 274 | 241 | 166
United States | Operating Segments | Pharmaceutical segment | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 119 | 89 | 4
United States | Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 32 | 51 | 60
United States | Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1 | 1 | 2
United States | Operating Segments | Pharmaceutical segment | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 350 | 329 | 312
United States | Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 10 | 1,523 | 632
United States | Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 215 | 274 | 294
United States | Operating Segments | Pharmaceutical segment | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 81 | 79 | 78
United States | Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,151 | 1,248 | 1,404
United States | Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 223 | 355 | 367
United States | Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 688 | 693 | 824
United States | Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,804 | 1,822 | 1,758
United States | Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 700 | 710 | 667
United States | Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,104 | 1,112 | 1,091
United States | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 137 | 395 | 266
Int’l |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 31,635 | 32,077 | 26,279
Int’l | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 30,865 | 30,744 | 26,163
Int’l | Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 27,044 | 27,016 | 22,353
Int’l | Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 9,897 | 8,251 | 7,421
Int’l | Operating Segments | Pharmaceutical segment | Alliance revenue - Lynparza |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 592 | 532 | 473
Int’l | Operating Segments | Pharmaceutical segment | Alliance revenue - Lenvima |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 303 | 297 | 287
Int’l | Operating Segments | Pharmaceutical segment | Welireg |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 10 | 0 | 0
Int’l | Operating Segments | Pharmaceutical segment | Alliance revenue - Reblozyl |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 43 | 43 | 17
Int’l | Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 6,803 | 4,832 | 3,792
Int’l | Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 531 | 518 | 506
Int’l | Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 276 | 275 | 334
Int’l | Operating Segments | Pharmaceutical segment | Vaxneuvance |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 103 | 7 | 0
Int’l | Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 285 | 256 | 346
Int’l | Operating Segments | Pharmaceutical segment | Vaqta |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 61 | 78 | 79
Int’l | Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 686 | 762 | 770
Int’l | Operating Segments | Pharmaceutical segment | Prevymis |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 341 | 240 | 218
Int’l | Operating Segments | Pharmaceutical segment | Dificid |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 28 | 22 | 10
Int’l | Operating Segments | Pharmaceutical segment | Zerbaxa |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 100 | 79 | (5)
Int’l | Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 181 | 187 | 199
Int’l | Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 211 | 238 | 258
Int’l | Operating Segments | Pharmaceutical segment | Alliance revenue - Adempas/Verquvo |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 16 | 12 | 30
Int’l | Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 255 | 238 | 252
Int’l | Operating Segments | Pharmaceutical segment | Lagevrio |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,418 | 4,161 | 320
Int’l | Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 268 | 359 | 474
Int’l | Operating Segments | Pharmaceutical segment | Belsomra |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 150 | 179 | 241
Int’l | Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 710 | 706 | 825
Int’l | Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 187 | 207 | 299
Int’l | Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,039 | 1,565 | 1,920
Int’l | Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 954 | 1,344 | 1,597
Int’l | Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,596 | 1,628 | 1,690
Int’l | Operating Segments | Animal Health |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,821 | 3,728 | 3,810
Int’l | Operating Segments | Animal Health | Livestock |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,637 | 2,590 | 2,628
Int’l | Operating Segments | Animal Health | Companion Animal |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,184 | 1,138 | 1,182
Int’l | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | $ 770 | $ 1,333 | $ 116

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