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Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Derivative [Line Items]
Pretax net unrealized gain on derivatives maturing within the next 12 months estimated to be reclassified from AOCI to sales	$ (161)		$ (161)
Equity investments without readily determinable fair values	848	$ 863	848	$ 863
Unrealized gains recognized on investments in equity securities without readily determinable fair value			12	7
Unrealized losses recognized on investments in equity securities without readily determinable fair values			25	24
Cumulative unrealized gains on investments	302		302
Cumulative unrealized losses on investments	89		89
Loss (income) from investments in equity securities, net	31	33	(169)	(240)
Payments			(148)	(117)
Fair value of loans payable and long-term debt, including current portion	35,200		35,200		$ 32,000
Debt, carrying amount	38,100		38,100		35,100
Factored accounts receivable			3,100		3,000
Cash collateral received from counterparties	0		0		3
Lyfnua
Derivative [Line Items]
Payments			(22)
Sanofi Pasteur
Derivative [Line Items]
Payments			(126)
Equity Funds
Derivative [Line Items]
Equity securities held through ownership interest in investments funds	328	467	328	467
Loss (income) from investments in equity securities, net	(21)	$ 93	(26)	$ 66
Accounts Receivable Factoring Collections
Derivative [Line Items]
Restricted cash	42		42		44
Level 2
Derivative [Line Items]
Cash equivalents	$ 13,600		$ 13,600		$ 6,000
Maximum | Derivatives Designated as Hedging Instruments
Derivative [Line Items]
Maximum average period of maturities of contracts in years (less than)			2 years
Maximum | Derivatives Not Designated as Hedging Instruments
Derivative [Line Items]
Maximum average period of maturities of contracts in years (less than)			6 months

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