Acquisitions, Divestitures, Equity-Method Investments, Licensing Arrangement, Collaborative Arrangements and Research and Development Arrangement - Acquisitions (Details) $ / shares in Units, $ in Millions										1 Months Ended	3 Months Ended					11 Months Ended	12 Months Ended						15 Months Ended
		Dec. 31, 2023 USD ($)		Dec. 14, 2023 USD ($) medicine $ / shares	Oct. 05, 2022 USD ($) $ / shares	Oct. 03, 2022 USD ($) $ / shares	Jun. 09, 2022 USD ($)	Mar. 11, 2022 USD ($) $ / shares	Nov. 17, 2021 USD ($) $ / shares	Nov. 30, 2021	Dec. 31, 2023 USD ($)		Dec. 31, 2022 USD ($)		Apr. 03, 2022 USD ($)	Nov. 16, 2021	Dec. 31, 2023 USD ($)		Dec. 31, 2022 USD ($)		Dec. 31, 2021 USD ($)		Dec. 31, 2023 USD ($)		Dec. 31, 2020 USD ($)
Business Acquisition [Line Items]
Business acquisition, cash payment, net of cash acquired																	$ 43,430		$ 22,997		$ 0
Uncertain tax positions		$ 4,802	[1]								$ 4,802	[1]	$ 4,494	[1]			4,802	[1]	4,494	[1]	6,068	[1]	$ 4,802	[1]	$ 5,595
Goodwill	[2]	$ 67,783									67,783		51,375				67,783		51,375		49,208		67,783
Acquired in-process research and development expenses																	194		953		3,469
Collaborative Arrangement [Member]
Business Acquisition [Line Items]
Acquired in-process research and development expenses	[3]																$ 13		$ 339		$ 1,056
Biohaven Ltd [Member] | Collaborative Arrangement [Member]
Business Acquisition [Line Items]
Tiered royalties, annual net sales threshold						$ 5,250
Potential milestone payments						$ 1,100
Subsequent reduction of milestone payments																							$ 608
Biohaven Ltd [Member]
Business Acquisition [Line Items]
Ownership percentage		1.30%
Biohaven [Member]
Business Acquisition [Line Items]
Ownership percentage										2.60%
Trillium [Member]
Business Acquisition [Line Items]
Ownership percentage																2.00%
ReViral [Member]
Business Acquisition [Line Items]
Asset acquisition, consideration transferred							$ 536
Payments to acquire asset							436
Payment for asset acquisition, base payment							425
Asset acquisition, contingent consideration							100
Acquired in-process research and development expenses							$ 426
Trillium [Member]
Business Acquisition [Line Items]
Asset acquisition, consideration transferred									$ 2,000
Acquired in-process research and development expenses									$ 2,100
Asset acquisition, share price (in dollars per share) | $ / shares									$ 18.50
Asset acquisition, assets acquired									$ 256
Asset acquisition, liabilities assumed									$ 81
Seagen [Member]
Business Acquisition [Line Items]
Business acquisition, per share in cash (in dollars per share) | $ / shares				$ 229
Business acquisition, cash payment, gross				$ 44,200
Business acquisition, cash payment, net of cash acquired				$ 43,400
Number of approved medicines | medicine				4
Gross contractual amount receivable				$ 597
Net deferred tax liabilities				6,100
Uncertain tax positions				56
Net deferred tax liabilities, gross				(7,500)
Deferred tax assets				1,400
Goodwill				16,126
Inventories	[4]			$ 4,195
Seagen [Member] | Restructuring Charges and Acquisition-Related Costs [Member]
Business Acquisition [Line Items]
Post closing compensation expense											$ 476
GBT [Member]
Business Acquisition [Line Items]
Business acquisition, per share in cash (in dollars per share) | $ / shares					$ 68.50
Business acquisition, cash payment, gross					$ 5,700
Business acquisition, cash payment, net of cash acquired					5,200
Net deferred tax liabilities					516
Intangible assets					4,400
Goodwill					1,100
Inventories					$ 644
Acquired inventory, selling period					3 years
Assumed long-term debt, paid in full					$ 331
GBT [Member] | Restructuring Charges and Acquisition-Related Costs [Member]
Business Acquisition [Line Items]
Post closing compensation expense					136								$ 136
Biohaven [Member]
Business Acquisition [Line Items]
Business acquisition, per share in cash (in dollars per share) | $ / shares						$ 148.50
Business acquisition, cash payment, gross						$ 11,500
Net deferred tax liabilities						544
Intangible assets						12,100
Goodwill						823
Inventories						$ 813
Acquired inventory, selling period						2 years
Assumed long-term debt, paid in full						$ 1,400
Repayment of assumed debt						863
Business acquisition, equity consideration						495
Consideration transferred, including equity interest held prior to business combination						11,800
Fair value of previously held equity interest in acquiree						300
Trade accounts receivable						398
Other current liabilities						526
Arena [Member]
Business Acquisition [Line Items]
Business acquisition, per share in cash (in dollars per share) | $ / shares								$ 100
Business acquisition, cash payment, gross								$ 6,600
Business acquisition, cash payment, net of cash acquired								6,200
Net deferred tax liabilities								490
Intangible assets								5,500
Goodwill								1,000
Arena [Member] | Restructuring Charges and Acquisition-Related Costs [Member]
Business Acquisition [Line Items]
Post closing compensation expense								138							$ 138
Developed Technology Rights [Member] | Seagen [Member]
Business Acquisition [Line Items]
Acquired intangible assets, useful life				18 years
Developed Technology Rights [Member] | GBT [Member]
Business Acquisition [Line Items]
Intangible assets					$ 1,400
Acquired intangible assets, useful life					6 years
Developed Technology Rights [Member] | Biohaven [Member]
Business Acquisition [Line Items]
Intangible assets						$ 11,600
Acquired intangible assets, useful life						11 years
IPR&D [Member] | GBT [Member]
Business Acquisition [Line Items]
Intangible assets					$ 3,000
IPR&D [Member] | Biohaven [Member]
Business Acquisition [Line Items]
Intangible assets						$ 450
IPR&D [Member] | Arena [Member]
Business Acquisition [Line Items]
Intangible assets								5,000
Licensing Agreements [Member] | Arena [Member]
Business Acquisition [Line Items]
Intangible assets								$ 460

[1] In 2023, included in Income taxes payable ($94 million), Other current assets ($1 million), Noncurrent deferred tax assets and other noncurrent tax assets ($1.3 billion), Noncurrent deferred tax liabilities ($4 million) and Other taxes payable ($3.4 billion). In 2022, included in Income taxes payable ($40 million), Other current assets ($3 million), Noncurrent deferred tax assets and other noncurrent tax assets ($1.2 billion), Noncurrent deferred tax liabilities ($5 million) and Other taxes payable ($3.2 billion).

[2] Our goodwill balance continues to be assigned within the Biopharma reportable segment.

[3] Primarily relates to upfront payments to our partners as well as premiums paid on our equity investments in the common stock of our partners.

[4] Comprised of $1.0 billion current inventories and $3.1 billion noncurrent inventories.