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Financial Instruments - Information on Debt and Equity Securities (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | $ 536 | $ 337
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 536 | 337
Equity securities | 920 | 764
Total debt and publicly traded equity securities, fair value | 1,456 | 1,101
Unrealized net gains (losses) | (30) | 411
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 348 | 252
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 348 | 252
U.S. government and agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 188 | 72
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 188 | 72
Corporate notes and bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 0 | 13
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | $ 0 | $ 13

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