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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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