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Financial Instruments - Narrative (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Apr. 30, 2024 USD ($) interest_rate_swap
Derivative [Line Items] |  |  |  |
Derivative, notional amount | $ 32,220 |  | $ 30,551 |
Pretax net unrealized gain on derivatives maturing within the next 12 months estimated to be reclassified from AOCI to sales | 113 |  |  |
Equity investments without readily determinable fair values | 851 | $ 942 |  |
Unrealized gains recognized on investments in equity securities without readily determinable fair value | 4 | 1 |  |
Unrealized losses recognized on investments in equity securities without readily determinable fair values | 5 | 21 |  |
Cumulative unrealized gains on investments | 297 |  |  |
Cumulative unrealized losses on investments | 69 |  |  |
Income from investments in equity securities, net | (143) | (450) |  |
Fair value of loans payable and long-term debt, including current portion | 30,400 |  | 32,000 |
Debt, carrying amount | 34,200 |  | 35,100 |
Factored accounts receivable | 2,700 |  | 3,000 |
Cash collateral received from counterparties | 58 |  | 3 |
Equity Funds |  |  |  |
Derivative [Line Items] |  |  |  |
Equity securities held through ownership interest in investments funds | 396 | 725 |  |
Income from investments in equity securities, net | 2 | $ (132) |  |
Accounts Receivable Factoring Collections |  |  |  |
Derivative [Line Items] |  |  |  |
Restricted cash | $ 43 |  | 44 |
Senior Notes | 4.50% Notes Due 2033 |  |  |  |
Derivative [Line Items] |  |  |  |
Stated interest rate | 4.50% |  |  |
Level 2 |  |  |  |
Derivative [Line Items] |  |  |  |
Cash equivalents | $ 4,600 |  | 6,000 |
Interest rate swap contracts | Subsequent Event |  |  |  |
Derivative [Line Items] |  |  |  |
Number of interest rate swaps | interest_rate_swap |  |  |  | 2
Interest rate swap contracts | 4.50% note due 2033 |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | 1,000 |  |  |
Interest rate swap contracts | 4.50% note due 2033 | Subsequent Event |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount |  |  |  | $ 250
Derivatives Designated as Hedging Instruments |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | 13,424 |  | 12,754 |
Derivatives Designated as Hedging Instruments | Interest rate swap contracts |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | 1,000 |  | 1,000 |
Derivatives Not Designated as Hedging Instruments |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | $ 18,796 |  | $ 17,797 |
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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