Borrowings - Short-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Short-term debt disclosures
Commercial paper	$ 900
Short-term loans	43	$ 130
Long-term debt - current maturities	6,632	7,053
Short-term Debt, Total	$ 7,575	$ 7,183
Commercial paper
Short-term debt disclosures
Weighted-average interest rates for short-term debt (as a percent)	0.10%
Short-term loans
Short-term debt disclosures
Weighted-average interest rates for short-term debt (as a percent)	3.80%	5.70%

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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