Debt and Credit Agreements - Activity Related to Long-Term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Movement, Debt Instruments [Roll Forward]
Long-term Debt as of December 31, 2021, Current Portion	$ 181
Long-term Debt as of December 31, 2021, Long-term Portion	16,185
Long-term Debt as of December 31, 2021, Total	16,366
Long-term Debt Repaid	(6)	$ (360)
Reclassifications	0
Hedging, Discount, Premium and Other Activity	(24)
Long-term Debt as of March 31, 2022, Current Portion	317
Long-term Debt as of March 31, 2022, Long-term Portion	16,019
Long-term Debt as of March 31, 2022, Total	16,336
Current Portion
Movement, Debt Instruments [Roll Forward]
Long-term Debt as of December 31, 2021, Current Portion	181
Long-term Debt Repaid	(6)
Reclassifications	142
Hedging, Discount, Premium and Other Activity	0
Long-term Debt as of March 31, 2022, Current Portion	317
Long-term Portion
Movement, Debt Instruments [Roll Forward]
Long-term Debt as of December 31, 2021, Long-term Portion	16,185
Long-term Debt Repaid
Reclassifications	(142)
Hedging, Discount, Premium and Other Activity	(24)
Long-term Debt as of March 31, 2022, Long-term Portion	$ 16,019

Long-term Debt, Increase (Decrease) Due To Reclassifications

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- Definition

Movement, Debt Instruments [Roll Forward]

+ References

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of short-term and long-term debt and lease obligation.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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