Goodwill and Other Intangibles - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Intangible Assets Excluding Goodwill [Line Items]
Other intangibles, net			$ 16,370	$ 18,011
Intangible asset impairment charges			39	$ 792	$ 1,749
Impairment, Intangible Asset, Indefinite-Lived (Excluding Goodwill), Statement of Income or Comprehensive Income [Extensible Enumeration]				Research and development	Research and development
Impairment, Intangible Asset, Finite-Lived, Statement of Income or Comprehensive Income [Extensible Enumeration]					Research and development
Amortization expense for intangible assets			2,400	$ 2,000	$ 2,100
Estimated aggregate amortization expense, 2025			2,400
Estimated aggregate amortization expense, 2026			2,300
Estimated aggregate amortization expense, 2027			2,100
Estimated aggregate amortization expense, 2028			1,800
Estimated aggregate amortization expense, 2029			1,500
IPR&D
Intangible Assets Excluding Goodwill [Line Items]
IPR&D intangible asset			430	6,816
Animal Health
Intangible Assets Excluding Goodwill [Line Items]
Other intangibles, net			4,300
gefapixant | IPR&D
Intangible Assets Excluding Goodwill [Line Items]
IPR&D impairment charges				779
Lyfnua
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			21
nemtabrutinib | IPR&D
Intangible Assets Excluding Goodwill [Line Items]
IPR&D intangible asset			418
IPR&D impairment charges	$ 780	$ 807			1,600
Product rights
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			10,922	5,878
Product rights | Reblozyl
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			2,800
Product rights | Zerbaxa
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			260
Product rights | Animal Health
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			1,700
Product rights | Winrevair
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			5,900
Trade names
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			1,927	2,105
Trade names | Animal Health
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			1,900
Licenses and other
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			3,091	$ 3,212
Licenses and other | Lynparza
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			1,200
Licenses and other | Lenvima
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			442
Licenses and other | Adempas
Intangible Assets Excluding Goodwill [Line Items]
Finite-lived intangible assets, net			$ 372
Licenses and other | derazantinib
Intangible Assets Excluding Goodwill [Line Items]
Intangible asset impairment charge related to finite-lived intangible asset					$ 80