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v3.21.1

Financial Instruments (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Short-Term Investments [Abstract] |  |
Short-term investments | $ 60 | $ 60
Short-term investments reclassified as other assets | 10 |
Fair Value of Debt Instruments [Abstract] |  |
Fair value of total debt | 29,300 | 31,900
Fair value of total debt in excess of (less than) carrying value | 2,600 | $ 5,100
Significant Other Observable Inputs (Level 2) [Member] | Time Deposits [Member] |  |
Short-Term Investments [Abstract] |  |
Short-term investments | $ 70 |

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