Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Finance Leases Average Interest Rate	5.60%
Total Long-term Debt Maturities, including current portion	$ 18,503	$ 18,533
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term Debt (Excluding Current Portion)	Long-term Debt (Excluding Current Portion)
Finance Leases	$ 10	$ 17
Less Debt Due within One Year	(606)	(558)	[1]
Long-term Debt (Excluding Current Portion)	$ 17,897	17,975	[1]
Notes
Debt Instrument [Line Items]
Average Interest Rates	4.30%
Total Long-term Debt Maturities, including current portion	$ 18,492	18,514
Equipment Obligations
Debt Instrument [Line Items]
Average Interest Rates	4.40%
Total Long-term Debt Maturities, including current portion	$ 1	$ 2

[1] See Note 20, Revision of Prior Period Financial Statements.