ACQUISITIONS, DIVESTITURES, LICENSING AND OTHER ARRANGEMENTS - Narrative (Details) $ / shares in Units, $ in Millions				1 Months Ended		12 Months Ended				24 Months Ended
	Mar. 18, 2024 USD ($) $ / shares	Feb. 26, 2024 USD ($) $ / shares	Jan. 23, 2024 USD ($)	Jan. 31, 2024 USD ($) right $ / shares	Oct. 31, 2023 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2014	Dec. 31, 2026	Feb. 28, 2025 USD ($)	Jan. 31, 2025 USD ($)
Business Acquisition [Line Items]
Royalty Income						$ 1,104	$ 862	$ 832
Keytruda Royalties
Business Acquisition [Line Items]
Percentage of net sales payable to alliance partner						2.50%	6.50%
LianBio Co. Ltd. | Mavacamten Rights
Business Acquisition [Line Items]
Payments for asset acquisitions					$ 445
Payments to acquire rights					$ 350
Bristol-Myers Squibb | Keytruda Royalties | Forecast | Subsequent Event
Business Acquisition [Line Items]
Payment and royalty allocation										75.00%
Ono | Keytruda Royalties | Forecast | Subsequent Event
Business Acquisition [Line Items]
Payment and royalty allocation										25.00%
Immatics
Business Acquisition [Line Items]
License and other arrangements upfront payments								150
Dragonfly
Business Acquisition [Line Items]
License and other arrangements upfront payments								175
BioArctic | Forecast
Business Acquisition [Line Items]
License and other arrangements upfront payments												$ 100
Contingent and regulatory milestone payments											$ 1,300
Mavacamten
Business Acquisition [Line Items]
Payment to extinguish future royalty obligation								295
Diabetes business - royalties
Business Acquisition [Line Items]
Royalty Income						$ 1,097	$ 862	810
Diabetes business - royalties | Supply Agreements
Business Acquisition [Line Items]
Royalty Income						1,200	960	924
Diabetes business - royalties | Amylin, Onglyza, and Farxiga
Business Acquisition [Line Items]
Business sale royalty expense						96	98	114
Mature products and other
Business Acquisition [Line Items]
Royalty Income						7	0	$ 22
Minimum | Diabetes business - royalties
Business Acquisition [Line Items]
Percentage of net sales payable to alliance partner									10.00%
Maximum | Diabetes business - royalties
Business Acquisition [Line Items]
Percentage of net sales payable to alliance partner									25.00%
Orum
Business Acquisition [Line Items]
Payments for asset acquisitions							100
Asset acquisition, consideration transferred, contingent consideration							80
Karuna
Business Acquisition [Line Items]
Asset acquisition, share price (in dollars per share) | $ / shares	$ 330.00
Payments for asset acquisitions	$ 14,027
Payments for asset acquisitions, net of cash acquired	$ 12,900
Karuna | Acquired IPRD
Business Acquisition [Line Items]
Payments for asset acquisitions						$ 12,100
RayzeBio
Business Acquisition [Line Items]
Business acquisition, share price (in usd per share) | $ / shares		$ 62.50
Acquisitions (Note 4)		$ 4,147
Total consideration allocated		3,600
Intangible assets		3,700
RayzeBio | In Process Research and Development
Business Acquisition [Line Items]
Identifiable assets acquired, indefinite-lived intangible assets		1,700
RayzeBio | Developed Technology Rights
Business Acquisition [Line Items]
Identifiable assets acquired, indefinite-lived intangible assets		$ 2,000
Mirati Therapeutics
Business Acquisition [Line Items]
Business acquisition, share price (in usd per share) | $ / shares				$ 58.00
Acquisitions (Note 4)			$ 4,801	$ 4,800
Total consideration allocated			4,100
Business combination, contingent value, number of rights received | right				1
Business combination, contingent value, share price (in dollars per share) | $ / shares				$ 12.00
Contingent consideration liability				$ 1,000
Business combination, contingent value payout, period				7 years
Inventories			215
Intangible assets			4,225
Mirati Therapeutics | In Process Research and Development
Business Acquisition [Line Items]
Intangible assets			3,500
Mirati Therapeutics | Acquired Marketed Product Rights
Business Acquisition [Line Items]
Intangible assets			640
Turning Point
Business Acquisition [Line Items]
Acquisitions (Note 4)							4,100
Total consideration allocated							$ 3,300
Inventory Purchase Price Fair Value Adjustment
Business Acquisition [Line Items]
Inventories			$ 148