Borrowings - Short-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Short-term debt disclosures
Short-term loans	$ 36	$ 130
Long-term debt - current maturities	6,406	7,053
Short-term Debt, Total	$ 6,442	$ 7,183
Short-term loans
Short-term debt disclosures
Weighted-average interest rates for short-term debt (as a percent)	5.10%	5.70%

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

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Amount of borrowings from a bank classified as other, maturing within one year or operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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