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Financial Instruments - Information on Debt and Equity Securities (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | $ 337 | $ 569
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 337 | 569
Publicly traded equity securities | 764 | 1,284
Total debt and publicly traded equity securities, fair value | 1,101 | 1,853
Unrealized net gains (losses) | 411 | (462)
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 252 | 498
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 252 | 498
U.S. government and agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 72 | 68
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | 72 | 68
Corporate notes and bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Debt securities, amortized cost | 13 | 3
Debt securities, gross unrealized gains | 0 | 0
Debt securities, gross unrealized losses | 0 | 0
Debt securities, fair value | $ 13 | $ 3

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