Contingencies and Environmental Liabilities (Details) $ in Millions		1 Months Ended		2 Months Ended	5 Months Ended	12 Months Ended
	Dec. 19, 2022	Jul. 31, 2023 motion	Jun. 30, 2023	May 31, 2023 patent	Oct. 31, 2024 patent	Dec. 31, 2024 USD ($) case Plaintiff	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Environmental Loss Contingency Statement Of Financial Position Extensible Enumeration Not Disclosed Flag						liabilities
Accrued liabilities for environmental matters | $						$ 41	$ 42
Term for paying off environmental liabilities						15 years
Aggregate possible expenditure on environmental matters in excess of amounts accrued | $						$ 46
Legal Defense Costs
Loss Contingencies [Line Items]
Legal defense costs reserve | $						$ 225	$ 210
Commercial and Other Litigation | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims						2
Loss contingency, number of plaintiffs | Plaintiff						2
The Johns Hopkins University
Loss Contingencies [Line Items]
Number of patents allegedly infringed | patent				9
Number of patents allegedly infringed under review | patent					9
Qui Tam | United States | Settled Litigation
Loss Contingencies [Line Items]
Loss contingency, motion for summary judgements granted | motion		2
Gardasil/Gardasil 9 | United States | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims						225
Gardasil/Gardasil 9 | Outside of the United States | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims						15
RotaTeq | United States | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, number of plaintiffs						35
Bridion | Patents
Loss Contingencies [Line Items]
Loss contingency, claims settled (in cases)						5
Bridion | Patents | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims						2
Loss contingency, trial period	1 day
Bridion | Patents | Settled Litigation
Loss Contingencies [Line Items]
Patent extension, term			5 years
Januvia/Janumet
Loss Contingencies [Line Items]
Loss contingency, claims settled (in cases)						26
Dr. Scholl's | United States | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, pending claims						415