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Segment Reporting - Sales of Company's Products (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Segment Reporting Information [Line Items] |  |  |
Sales | $ 40,122 | $ 39,807 | $ 39,498
Proceeds from sale of intangible assets | 85 | 170 |
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 39,662 | 39,013 | 38,449
Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 35,390 | 35,151 | 34,782
Operating Segments | Pharmaceutical segment | Zetia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,344 | 2,560 | 2,526
Operating Segments | Pharmaceutical segment | Vytorin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 751 | 1,141 | 1,251
Operating Segments | Pharmaceutical segment | Atozet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 225 | 146 | 36
Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 300 | 169 | 30
Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,737 | 3,908 | 3,863
Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,158 | 2,201 | 2,151
Operating Segments | Pharmaceutical segment | NuvaRing |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 761 | 777 | 732
Operating Segments | Pharmaceutical segment | Implanon/Nexplanon |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 686 | 606 | 588
Operating Segments | Pharmaceutical segment | Follistim AQ |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 298 | 355 | 383
Operating Segments | Pharmaceutical segment | Zepatier |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,660 | 555 | 0
Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,204 | 1,387 | 1,511
Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 704 | 482 | 353
Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 636 | 595 | 487
Operating Segments | Pharmaceutical segment | Invanz |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 602 | 561 | 569
Operating Segments | Pharmaceutical segment | Cancidas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 422 | 558 | 573
Operating Segments | Pharmaceutical segment | Cubicin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 382 | 1,087 | 1,127
Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 280 | 297 | 313
Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 837 | 1,268 | 1,794
Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 819 | 766 | 690
Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,809 | 1,402 | 566
Operating Segments | Pharmaceutical segment | Emend |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 556 | 549 | 535
Operating Segments | Pharmaceutical segment | Temodar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 271 | 283 | 312
Operating Segments | Pharmaceutical segment | Singulair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 732 | 915 | 931
Operating Segments | Pharmaceutical segment | Nasonex |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 387 | 537 | 858
Operating Segments | Pharmaceutical segment | Dulera |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 287 | 436 | 536
Operating Segments | Pharmaceutical segment | Cozaar/Hyzaar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 484 | 511 | 667
Operating Segments | Pharmaceutical segment | Arcoxia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 363 | 450 | 471
Operating Segments | Pharmaceutical segment | Fosamax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 241 | 284 | 359
Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,308 | 2,173 | 1,908
Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,676 | 1,640 | 1,505
Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 821 | 641 | 542
Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 686 | 652 | 610
Operating Segments | Pharmaceutical segment | Zostavax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 668 | 685 | 749
Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 4,295 | 4,574 | 5,256
Operating Segments | Other segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 4,272 | 3,862 | 3,667
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 460 | 794 | 1,049
United States |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 17,424 | 18,478 | 17,519
United States | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 17,340 | 18,447 | 17,451
United States | Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 15,854 | 17,073 | 16,238
United States | Operating Segments | Pharmaceutical segment | Zetia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 352 | 1,588 | 1,612
United States | Operating Segments | Pharmaceutical segment | Vytorin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 124 | 473 | 479
United States | Operating Segments | Pharmaceutical segment | Atozet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 1 | 2
United States | Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,153 | 2,286 | 2,263
United States | Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 863 | 984 | 976
United States | Operating Segments | Pharmaceutical segment | NuvaRing |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 564 | 576 | 515
United States | Operating Segments | Pharmaceutical segment | Implanon/Nexplanon |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 496 | 420 | 367
United States | Operating Segments | Pharmaceutical segment | Follistim AQ |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 123 | 157 | 160
United States | Operating Segments | Pharmaceutical segment | Zepatier |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 771 | 488 | 0
United States | Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 565 | 721 | 797
United States | Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 239 | 77 | 0
United States | Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 309 | 284 | 212
United States | Operating Segments | Pharmaceutical segment | Invanz |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 361 | 329 | 322
United States | Operating Segments | Pharmaceutical segment | Cancidas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 20 | 25 | 24
United States | Operating Segments | Pharmaceutical segment | Cubicin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 189 | 906 | 1,030
United States | Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 10 | 4 | 8
United States | Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,309 | 792 | 393
United States | Operating Segments | Pharmaceutical segment | Emend |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 342 | 356 | 326
United States | Operating Segments | Pharmaceutical segment | Temodar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 16 | 15 | 7
United States | Operating Segments | Pharmaceutical segment | Singulair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 40 | 40 | 39
United States | Operating Segments | Pharmaceutical segment | Nasonex |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 54 | 184 | 449
United States | Operating Segments | Pharmaceutical segment | Dulera |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 261 | 412 | 515
United States | Operating Segments | Pharmaceutical segment | Cozaar/Hyzaar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 18 | 16 | 30
United States | Operating Segments | Pharmaceutical segment | Arcoxia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 0 | 0 | 0
United States | Operating Segments | Pharmaceutical segment | Fosamax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 6 | 5 | 12
United States | Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,565 | 1,780 | 1,520
United States | Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,374 | 1,362 | 1,290
United States | Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 581 | 447 | 378
United States | Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 481 | 482 | 447
United States | Operating Segments | Pharmaceutical segment | Zostavax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 422 | 518 | 592
United States | Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,246 | 1,345 | 1,473
United States | Operating Segments | Other segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,486 | 1,374 | 1,213
United States | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 84 | 31 | 68
Int’l |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 22,698 | 21,329 | 21,979
Int’l | Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 22,321 | 20,566 | 20,998
Int’l | Operating Segments | Pharmaceutical segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 19,536 | 18,077 | 18,544
Int’l | Operating Segments | Pharmaceutical segment | Zetia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 992 | 972 | 914
Int’l | Operating Segments | Pharmaceutical segment | Vytorin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 627 | 668 | 771
Int’l | Operating Segments | Pharmaceutical segment | Atozet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 225 | 146 | 34
Int’l | Operating Segments | Pharmaceutical segment | Adempas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 300 | 169 | 30
Int’l | Operating Segments | Pharmaceutical segment | Januvia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,584 | 1,622 | 1,601
Int’l | Operating Segments | Pharmaceutical segment | Janumet |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,296 | 1,217 | 1,175
Int’l | Operating Segments | Pharmaceutical segment | NuvaRing |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 197 | 202 | 216
Int’l | Operating Segments | Pharmaceutical segment | Implanon/Nexplanon |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 191 | 186 | 221
Int’l | Operating Segments | Pharmaceutical segment | Follistim AQ |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 174 | 197 | 223
Int’l | Operating Segments | Pharmaceutical segment | Zepatier |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 888 | 67 | 0
Int’l | Operating Segments | Pharmaceutical segment | Isentress/Isentress HD |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 639 | 666 | 714
Int’l | Operating Segments | Pharmaceutical segment | Bridion |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 465 | 405 | 353
Int’l | Operating Segments | Pharmaceutical segment | Noxafil |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 327 | 312 | 275
Int’l | Operating Segments | Pharmaceutical segment | Invanz |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 241 | 233 | 247
Int’l | Operating Segments | Pharmaceutical segment | Cancidas |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 402 | 533 | 548
Int’l | Operating Segments | Pharmaceutical segment | Cubicin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 193 | 181 | 97
Int’l | Operating Segments | Pharmaceutical segment | Primaxin |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 270 | 293 | 305
Int’l | Operating Segments | Pharmaceutical segment | Remicade |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 837 | 1,268 | 1,794
Int’l | Operating Segments | Pharmaceutical segment | Simponi |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 819 | 766 | 690
Int’l | Operating Segments | Pharmaceutical segment | Keytruda |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 1,500 | 610 | 173
Int’l | Operating Segments | Pharmaceutical segment | Emend |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 213 | 193 | 209
Int’l | Operating Segments | Pharmaceutical segment | Temodar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 256 | 268 | 306
Int’l | Operating Segments | Pharmaceutical segment | Singulair |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 692 | 874 | 892
Int’l | Operating Segments | Pharmaceutical segment | Nasonex |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 333 | 352 | 409
Int’l | Operating Segments | Pharmaceutical segment | Dulera |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 26 | 24 | 21
Int’l | Operating Segments | Pharmaceutical segment | Cozaar/Hyzaar |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 466 | 494 | 637
Int’l | Operating Segments | Pharmaceutical segment | Arcoxia |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 363 | 450 | 471
Int’l | Operating Segments | Pharmaceutical segment | Fosamax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 235 | 279 | 347
Int’l | Operating Segments | Pharmaceutical segment | Gardasil/Gardasil 9 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 743 | 393 | 388
Int’l | Operating Segments | Pharmaceutical segment | ProQuad/M-M-R II/Varivax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 303 | 279 | 214
Int’l | Operating Segments | Pharmaceutical segment | Pneumovax 23 |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 240 | 193 | 164
Int’l | Operating Segments | Pharmaceutical segment | RotaTeq |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 204 | 169 | 163
Int’l | Operating Segments | Pharmaceutical segment | Zostavax |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 246 | 168 | 157
Int’l | Operating Segments | Pharmaceutical segment | Other pharmaceutical |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 3,049 | 3,228 | 3,785
Int’l | Operating Segments | Other segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | 2,785 | 2,489 | 2,454
Int’l | Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Sales | $ 377 | $ 763 | $ 981

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