Other (Income)/Deductions—Net - Footnotes (Detail) - USD ($)			3 Months Ended
		Dec. 14, 2023	Mar. 31, 2024	Apr. 02, 2023	Dec. 31, 2023	May 31, 2023
Loss Contingencies [Line Items]
Commercial paper, principal amount			$ 6,933,000,000		$ 7,965,000,000
Net unrealized (gains)/losses during the reporting period on equity securities still held at the reporting date	[1]		188,000,000	$ 485,000,000
Intangible asset impairment charge			109,000,000
Seagen [Member]
Loss Contingencies [Line Items]
Commercial paper, principal amount					$ 8,000,000,000
Acquisitions of businesses, net of cash acquired		$ 43,400,000,000
Unsecured Debt [Member]
Loss Contingencies [Line Items]
Face amount of debt issued						$ 31,000,000,000
IPR&D [Member] | Biopharma [Member]
Loss Contingencies [Line Items]
Intangible asset impairment charge	[2]			128,000,000
License Agreements and Other [Member] | Biopharma [Member]
Loss Contingencies [Line Items]
Intangible asset impairment charge				120,000,000
Cerevel and BioNTech [Member]
Loss Contingencies [Line Items]
Net unrealized (gains)/losses during the reporting period on equity securities still held at the reporting date				363,000,000
Nimbus [Member]
Loss Contingencies [Line Items]
Dividend income				211,000,000
ViiV [Member] | Biopharma [Member]
Loss Contingencies [Line Items]
Dividend income			61,000,000	$ 92,000,000
Haleon [Member]
Loss Contingencies [Line Items]
Gain on sale of equity method investment			$ 150,000,000

[1] Included in net unrealized (gains)/losses are observable price changes on equity securities without readily determinable fair values. As of March 31, 2024, there were cumulative impairments and downward adjustments of $293 million and upward adjustments of $212 million. Impairments, downward and upward adjustments were not material to our operations in the first quarters of 2024 and 2023.

[2] Reflects intangible assets written down to fair value in 2024. Fair value was determined using the income approach, specifically the multi-period excess earnings method, also known as the discounted cash flow method. We started with a forecast of all the expected net cash flows for the asset and then applied an asset-specific discount rate to arrive at a net present value amount. Some of the more significant estimates and assumptions inherent in this approach include: the amount and timing of the projected net cash flows, which includes the expected impact of competitive, legal and/or regulatory forces on the product; the discount rate, which seeks to reflect the various risks inherent in the projected cash flows; and the tax rate, which seeks to incorporate the geographic diversity of the projected cash flows.