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Financial Instruments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Pretax net unrealized losses on derivatives maturing within the next 12 months estimated to be reclassified from AOCI to sales	$ 40
Equity investments without readily determinable fair values	832	$ 832
Unrealized gains recognized on investments in equity securities without readily determinable fair value	10	56
Unrealized losses recognized on investments in equity securities without readily determinable fair values	61	12
Cumulative upward price adjustment	299
Cumulative downward price adjustment	80
(Income) loss from investments in equity securities, net	(340)	1,419	$ (1,940)
Fair value of loans payable and long-term debt, including current portion	32,000	26,700
Debt, carrying amount	35,100	30,700
Factored accounts receivable	3,000	2,500
Cash collateral received from counterparties	3	66
Cash collateral advanced to counterparties		19
Equity Funds
Derivative [Line Items]
Equity securities held through ownership interests in investment funds	417	598	1,700
(Income) loss from investments in equity securities, net	106	1,000	$ (1,400)
Accounts Receivable Factoring Collections
Derivative [Line Items]
Funds collected from factoring of receivable, held in restricted cash	$ 44	67
Customer Concentration Risk \| Accounts Receivable \| McKesson Corporation
Derivative [Line Items]
Percentage of accounts receivable represented by customers with largest balances	21.00%
Customer Concentration Risk \| Accounts Receivable \| Cencora, Inc.
Derivative [Line Items]
Percentage of accounts receivable represented by customers with largest balances	20.00%
Customer Concentration Risk \| Accounts Receivable \| Cardinal Health, Inc.
Derivative [Line Items]
Percentage of accounts receivable represented by customers with largest balances	14.00%
Level 2
Derivative [Line Items]
Cash equivalents	$ 6,000	$ 11,300
Maximum \| Derivatives Designated as Hedging Instruments
Derivative [Line Items]
Term of derivative contract	2 years
Maximum \| Derivatives Not Designated as Hedging Instruments
Derivative [Line Items]
Maximum planning cycle of hedges (less than)	6 months