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v3.25.3

Segment Reporting - Schedule of Sales from Products (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Sales | $ 17,276 | $ 16,657 | $ 48,611 | $ 48,544
Increase in hedge revenue |  |  | (61) | 156
Revenue related to the sale of the marketing rights |  |  | 111 | 91
U.S. |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 10,012 | 8,736 | 27,371 | 24,089
Non-US |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 7,264 | 7,922 | 21,240 | 24,455
Operating Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 17,226 | 16,430 | 48,148 | 47,838
Operating Segments | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 15,611 | 14,943 | 43,299 | 43,358
Operating Segments | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 1,615 | 1,487 | 4,849 | 4,480
Operating Segments | U.S. |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 9,997 | 8,714 | 27,252 | 23,980
Operating Segments | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 9,493 | 8,227 | 25,747 | 22,563
Operating Segments | U.S. | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 504 | 487 | 1,505 | 1,417
Operating Segments | Non-US |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 7,230 | 7,716 | 20,897 | 23,858
Operating Segments | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 6,118 | 6,717 | 17,552 | 20,795
Operating Segments | Non-US | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 1,112 | 999 | 3,345 | 3,063
Operating Segments | Keytruda | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 8,142 | 7,429 | 23,303 | 21,646
Operating Segments | Keytruda | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 4,879 | 4,500 | 13,936 | 13,031
Operating Segments | Keytruda | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 3,263 | 2,929 | 9,367 | 8,614
Operating Segments | Alliance revenue - Lynparza | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 379 | 337 | 1,061 | 947
Operating Segments | Alliance revenue - Lynparza | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 184 | 161 | 503 | 449
Operating Segments | Alliance revenue - Lynparza | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 195 | 177 | 558 | 498
Operating Segments | Alliance revenue - Lenvima | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 258 | 251 | 781 | 755
Operating Segments | Alliance revenue - Lenvima | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 177 | 173 | 545 | 523
Operating Segments | Alliance revenue - Lenvima | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 81 | 78 | 236 | 233
Operating Segments | Welireg | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 196 | 139 | 496 | 349
Operating Segments | Welireg | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 161 | 127 | 422 | 320
Operating Segments | Welireg | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 35 | 12 | 74 | 29
Operating Segments | Alliance Revenue - Reblozyl | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 136 | 100 | 361 | 261
Operating Segments | Alliance Revenue - Reblozyl | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 111 | 82 | 299 | 215
Operating Segments | Alliance Revenue - Reblozyl | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 25 | 18 | 62 | 45
Operating Segments | Gardasil/Gardasil 9 | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 1,749 | 2,306 | 4,202 | 7,032
Operating Segments | Gardasil/Gardasil 9 | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 1,154 | 1,020 | 2,235 | 2,045
Operating Segments | Gardasil/Gardasil 9 | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 595 | 1,285 | 1,967 | 4,988
Operating Segments | ProQuad/M-M-R II/Varivax | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 684 | 703 | 1,832 | 1,891
Operating Segments | ProQuad/M-M-R II/Varivax | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 554 | 572 | 1,457 | 1,500
Operating Segments | ProQuad/M-M-R II/Varivax | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 130 | 131 | 374 | 391
Operating Segments | Vaxneuvance | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 226 | 239 | 685 | 647
Operating Segments | Vaxneuvance | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 134 | 137 | 409 | 397
Operating Segments | Vaxneuvance | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 91 | 103 | 276 | 251
Operating Segments | RotaTeq | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 204 | 193 | 554 | 572
Operating Segments | RotaTeq | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 141 | 131 | 366 | 388
Operating Segments | RotaTeq | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 63 | 62 | 187 | 185
Operating Segments | Capvaxive | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 244 | 47 | 480 | 47
Operating Segments | Capvaxive | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 238 | 47 | 473 | 47
Operating Segments | Capvaxive | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 7 | 0 | 8 | 0
Operating Segments | Pneumovax 23 | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 45 | 68 | 124 | 188
Operating Segments | Pneumovax 23 | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 10 | 19 | 13 | 36
Operating Segments | Pneumovax 23 | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 35 | 49 | 111 | 152
Operating Segments | Bridion | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 439 | 420 | 1,341 | 1,315
Operating Segments | Bridion | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 392 | 339 | 1,181 | 1,020
Operating Segments | Bridion | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 47 | 81 | 161 | 296
Operating Segments | Prevymis | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 266 | 208 | 702 | 570
Operating Segments | Prevymis | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 128 | 101 | 345 | 265
Operating Segments | Prevymis | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 138 | 107 | 357 | 305
Operating Segments | Zerbaxa | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 81 | 64 | 225 | 182
Operating Segments | Zerbaxa | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 49 | 39 | 136 | 106
Operating Segments | Zerbaxa | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 32 | 26 | 89 | 77
Operating Segments | Dificid | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 43 | 96 | 222 | 261
Operating Segments | Dificid | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 30 | 83 | 185 | 231
Operating Segments | Dificid | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 13 | 13 | 37 | 30
Operating Segments | Winrevair | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 360 | 149 | 976 | 219
Operating Segments | Winrevair | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 335 | 147 | 926 | 216
Operating Segments | Winrevair | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 25 | 3 | 49 | 3
Operating Segments | Alliance revenue - Adempas/Verquvo | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 112 | 102 | 340 | 306
Operating Segments | Alliance revenue - Adempas/Verquvo | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 103 | 96 | 308 | 283
Operating Segments | Alliance revenue - Adempas/Verquvo | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 8 | 7 | 32 | 22
Operating Segments | Adempas | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 82 | 72 | 229 | 214
Operating Segments | Adempas | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 0 | 0 | 0
Operating Segments | Adempas | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 82 | 72 | 229 | 214
Operating Segments | Lagevrio | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 138 | 383 | 323 | 843
Operating Segments | Lagevrio | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 24 | 84 | 90 | 144
Operating Segments | Lagevrio | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 114 | 299 | 233 | 699
Operating Segments | Isentress/Isentress HD | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 82 | 102 | 258 | 302
Operating Segments | Isentress/Isentress HD | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 44 | 54 | 144 | 147
Operating Segments | Isentress/Isentress HD | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 37 | 48 | 114 | 155
Operating Segments | Delstrigo | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 77 | 65 | 228 | 180
Operating Segments | Delstrigo | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 13 | 15 | 42 | 42
Operating Segments | Delstrigo | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 64 | 50 | 185 | 139
Operating Segments | Pifeltro | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 43 | 42 | 128 | 123
Operating Segments | Pifeltro | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 29 | 31 | 86 | 86
Operating Segments | Pifeltro | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 14 | 12 | 43 | 37
Operating Segments | Belsomra | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 47 | 78 | 137 | 177
Operating Segments | Belsomra | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 28 | 20 | 59 | 53
Operating Segments | Belsomra | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 19 | 58 | 77 | 124
Operating Segments | Simponi | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 189 | 0 | 545
Operating Segments | Simponi | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 0 | 0 | 0
Operating Segments | Simponi | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 189 | 0 | 545
Operating Segments | Remicade | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 41 | 0 | 115
Operating Segments | Remicade | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 0 | 0 | 0
Operating Segments | Remicade | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 0 | 41 | 0 | 115
Operating Segments | Januvia | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 382 | 278 | 1,302 | 1,102
Operating Segments | Januvia | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 258 | 67 | 819 | 428
Operating Segments | Januvia | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 124 | 211 | 483 | 674
Operating Segments | Janumet | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 243 | 204 | 741 | 679
Operating Segments | Janumet | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 78 | 15 | 210 | 70
Operating Segments | Janumet | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 165 | 190 | 530 | 610
Operating Segments | Other pharmaceutical | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 953 | 638 | 2,268 | 1,890
Operating Segments | Other pharmaceutical | U.S. | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 239 | 167 | 558 | 521
Operating Segments | Other pharmaceutical | Non-US | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 716 | 466 | 1,713 | 1,364
Operating Segments | Livestock | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 1,023 | 886 | 2,909 | 2,573
Operating Segments | Livestock | U.S. | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 213 | 194 | 598 | 529
Operating Segments | Livestock | Non-US | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 811 | 692 | 2,312 | 2,044
Operating Segments | Companion Animal | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 592 | 601 | 1,940 | 1,907
Operating Segments | Companion Animal | U.S. | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 291 | 293 | 907 | 888
Operating Segments | Companion Animal | Non-US | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 301 | 307 | 1,033 | 1,019
Operating Segments | Alliance revenue - Koselugo | Pharmaceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 214 | 39 | 301 | 114
Corporate, Non-Segment |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 50 | 227 | 463 | 706
Corporate, Non-Segment | U.S. |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | 15 | 22 | 119 | 109
Corporate, Non-Segment | Non-US |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Sales | $ 34 | $ 206 | $ 343 | $ 597

X
- Definition Increase (Decrease) In Hedge Revenue + References No definition available. + Details
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Namespace Prefix: | mrk_
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Balance Type: | debit
Period Type: | duration

X
- Definition The cash inflow from disposal of asset without physical form usually arising from contractual or other legal rights, excluding goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-12 + Details
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Balance Type: | debit
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X
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. 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