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Fair Value Measurements - Carrying Amounts of Long-term Debt (Details) - USD ($) $ in Millions | Jun. 30, 2022 | Dec. 31, 2021
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Carrying Value |  |
Fair value and related carrying amounts of long-term debt and other long-term obligations |  |
Long-term debt and other long-term obligations | $ 21,201 | $ 23,946
Fair Value |  |
Fair value and related carrying amounts of long-term debt and other long-term obligations |  |
Long-term debt and other long-term obligations | $ 20,048 | $ 27,043

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