v3.21.1

Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Financial instruments
Long-term debt, including current maturities	$ 7,620	$ 7,807
Carrying amount
Financial instruments
Cash and cash equivalents	1,066	1,154
Restricted cash and cash equivalents	388	406
Long-term debt, including current maturities	7,620	7,807
Fair value
Financial instruments
Cash and cash equivalents	1,066	1,154
Restricted cash and cash equivalents	388	406
Long-term debt, including current maturities	$ 5,503	$ 4,820

X

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

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

+ References

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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