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Financial Instruments - Information on Available-for-sale Investments (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt securities, amortized cost | $ 117 |  | $ 337
Debt securities, unrealized gains | 0 |  | 0
Debt securities, unrealized losses | 0 |  | 0
Debt securities, fair value | 117 |  | 337
Publicly traded equity securities, fair value | 908 |  | 764
Total debt and publicly traded equity securities, fair value | 1,025 |  | 1,101
Unrealized net gains (losses) | 143 | $ 338 |
Commercial paper |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt securities, amortized cost | 40 |  | 252
Debt securities, unrealized gains | 0 |  | 0
Debt securities, unrealized losses | 0 |  | 0
Debt securities, fair value | 40 |  | 252
U.S. government and agency securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt securities, amortized cost | 77 |  | 72
Debt securities, unrealized gains | 0 |  | 0
Debt securities, unrealized losses | 0 |  | 0
Debt securities, fair value | 77 |  | 72
Corporate notes and bonds |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt securities, amortized cost | 0 |  | 13
Debt securities, unrealized gains | 0 |  | 0
Debt securities, unrealized losses | 0 |  | 0
Debt securities, fair value | $ 0 |  | $ 13

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