Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Finance Leases Average Interest Rate	4.70%
Total Long-term Debt Maturities, including current portion	$ 18,873	$ 18,503
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term Debt (Excluding Current Portion)	Long-term Debt (Excluding Current Portion)
Finance Leases	$ 15	$ 10
Less Debt Due within One Year	(708)	(606)
Long-term Debt (Excluding Current Portion)	$ 18,165	17,897
Notes
Debt Instrument [Line Items]
Average Interest Rates	4.40%
Total Long-term Debt Maturities, including current portion	$ 18,858	18,492
Equipment Obligations
Debt Instrument [Line Items]
Average Interest Rates	4.30%
Total Long-term Debt Maturities, including current portion	$ 0	$ 1