Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Finance Leases Average Interest Rate	6.00%
Subtotal Long-term Debt (Including Current Portion)	$ 18,047	$ 16,366
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term Debt (Excluding Current Portion)	Long-term Debt (Excluding Current Portion)
Finance Leases	$ 29	$ 47
Less Debt Due within One Year	(151)	(181)
Long-term Debt (Excluding Current Portion)	$ 17,896	16,185
Notes
Debt Instrument [Line Items]
Debt Average Interest Rates	4.20%
Subtotal Long-term Debt (Including Current Portion)	$ 17,877	16,166
Equipment Obligations
Debt Instrument [Line Items]
Debt Average Interest Rates	6.20%
Subtotal Long-term Debt (Including Current Portion)	$ 141	$ 153

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

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The average effective interest rate during the reporting period.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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

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

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