Borrowings - Long-Term Debt, Components (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Borrowings
Long-term debt, gross	$ 65,012	$ 62,286
Long-term debt excluding finance lease obligations	63,772	61,134
Less: net unamortized discount	791	806
Less: net unamortized debt issuance costs	199	185
Add: fair value adjustment	(209)	(36)
Total, including current maturities	63,813	61,259
Less: current maturities	7,009	6,424
Total	56,804	54,836
U.S. dollar
Borrowings
Long-term debt, gross	36,450	38,979
Euro
Borrowings
Long-term debt, gross	23,567	20,258
Maturing 2026 | U.S. dollar
Borrowings
Long-term debt, gross	$ 0	5,800
Debt instrument, weighted-average interest rate (as a percent)	3.70%
Maturing 2027 | U.S. dollar
Borrowings
Long-term debt, gross	$ 4,119	4,119
Debt instrument, weighted-average interest rate (as a percent)	3.30%
Maturing 2027 | Euro
Borrowings
Long-term debt, gross	$ 2,272	2,349
Debt instrument, weighted-average interest rate (as a percent)	2.30%
Maturing 2028 | U.S. dollar
Borrowings
Long-term debt, gross	$ 2,317	2,319
Debt instrument, weighted-average interest rate (as a percent)	4.80%
Maturing 2028 | Euro
Borrowings
Long-term debt, gross	$ 2,896	2,114
Debt instrument, weighted-average interest rate (as a percent)	1.30%
Maturing 2029 | U.S. dollar
Borrowings
Long-term debt, gross	$ 4,256	3,757
Debt instrument, weighted-average interest rate (as a percent)	3.70%
Maturing 2029 | Euro
Borrowings
Long-term debt, gross	$ 1,136	1,174
Debt instrument, weighted-average interest rate (as a percent)	1.50%
Maturing 2030 | U.S. dollar
Borrowings
Long-term debt, gross	$ 2,380	2,355
Debt instrument, weighted-average interest rate (as a percent)	3.20%
Maturing 2030 | Euro
Borrowings
Long-term debt, gross	$ 1,988	2,055
Debt instrument, weighted-average interest rate (as a percent)	1.70%
Maturing 2031 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,000	500
Debt instrument, weighted-average interest rate (as a percent)	4.50%
Maturing 2031 | Euro
Borrowings
Long-term debt, gross	$ 3,975	2,936
Debt instrument, weighted-average interest rate (as a percent)	2.80%
Maturing 2032 | U.S. dollar
Borrowings
Long-term debt, gross	$ 2,700	2,700
Debt instrument, weighted-average interest rate (as a percent)	4.60%
Maturing 2032 | Euro
Borrowings
Long-term debt, gross	$ 1,817	1,879
Debt instrument, weighted-average interest rate (as a percent)	0.70%
Maturing 2033 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,250	750
Debt instrument, weighted-average interest rate (as a percent)	4.70%
Maturing 2033 | Euro
Borrowings
Long-term debt, gross	$ 1,249	1,292
Debt instrument, weighted-average interest rate (as a percent)	3.20%
Maturing 2034 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,000	1,000
Debt instrument, weighted-average interest rate (as a percent)	4.90%
Maturing 2034 | Euro
Borrowings
Long-term debt, gross	$ 2,272	1,174
Debt instrument, weighted-average interest rate (as a percent)	2.40%
Maturing 2035 | U.S. dollar
Borrowings
Long-term debt, gross	$ 900	900
Debt instrument, weighted-average interest rate (as a percent)	5.20%
Maturing 2035 | Euro
Borrowings
Long-term debt, gross	$ 1,136	1,174
Debt instrument, weighted-average interest rate (as a percent)	3.80%
Maturing 2036 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,000	0
Debt instrument, weighted-average interest rate (as a percent)	5.00%
Maturing 2037 | Euro
Borrowings
Long-term debt, gross	$ 1,022	1,057
Debt instrument, weighted-average interest rate (as a percent)	3.50%
Maturing 2038 | U.S. dollar
Borrowings
Long-term debt, gross	$ 83	83
Debt instrument, weighted-average interest rate (as a percent)	8.00%
Maturing 2038 | Euro
Borrowings
Long-term debt, gross	$ 852	0
Debt instrument, weighted-average interest rate (as a percent)	3.90%
Maturing 2038 | Pound sterling
Borrowings
Long-term debt, gross	$ 996	1,009
Debt instrument, weighted-average interest rate (as a percent)	4.90%
Maturing 2039 | U.S. dollar
Borrowings
Long-term debt, gross	$ 2,745	2,745
Debt instrument, weighted-average interest rate (as a percent)	4.50%
Maturing 2040 | U.S. dollar
Borrowings
Long-term debt, gross	$ 650	650
Debt instrument, weighted-average interest rate (as a percent)	2.90%
Maturing 2040 | Euro
Borrowings
Long-term debt, gross	$ 965	998
Debt instrument, weighted-average interest rate (as a percent)	1.20%
Maturing 2042 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,107	1,107
Debt instrument, weighted-average interest rate (as a percent)	4.00%
Maturing 2043 | Euro
Borrowings
Long-term debt, gross	$ 1,136	1,174
Debt instrument, weighted-average interest rate (as a percent)	4.00%
Maturing 2044 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,000	1,000
Debt instrument, weighted-average interest rate (as a percent)	5.30%
Maturing 2045 | U.S. dollar
Borrowings
Long-term debt, gross	$ 27	27
Debt instrument, weighted-average interest rate (as a percent)	7.00%
Maturing 2045 | Euro
Borrowings
Long-term debt, gross	$ 852	881
Debt instrument, weighted-average interest rate (as a percent)	3.80%
Maturing 2046 | U.S. dollar
Borrowings
Long-term debt, gross	$ 650	650
Debt instrument, weighted-average interest rate (as a percent)	4.70%
Maturing 2049 | U.S. dollar
Borrowings
Long-term debt, gross	$ 3,000	3,000
Debt instrument, weighted-average interest rate (as a percent)	4.30%
Maturing 2050 | U.S. dollar
Borrowings
Long-term debt, gross	$ 750	750
Debt instrument, weighted-average interest rate (as a percent)	3.00%
Maturing 2052 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,400	1,400
Debt instrument, weighted-average interest rate (as a percent)	4.20%
Maturing 2053 | U.S. dollar
Borrowings
Long-term debt, gross	$ 650	650
Debt instrument, weighted-average interest rate (as a percent)	5.10%
Maturing 2054 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,400	1,400
Debt instrument, weighted-average interest rate (as a percent)	5.30%
Maturing 2055 | U.S. dollar
Borrowings
Long-term debt, gross	$ 1,000	1,000
Debt instrument, weighted-average interest rate (as a percent)	5.70%
Maturing 2056 | U.S. dollar
Borrowings
Long-term debt, gross	$ 750	0
Debt instrument, weighted-average interest rate (as a percent)	5.80%
Maturing 2096 | U.S. dollar
Borrowings
Long-term debt, gross	$ 316	316
Debt instrument, weighted-average interest rate (as a percent)	7.10%
Maturing 2030-2034 | Canadian dollars
Borrowings
Long-term debt, gross	$ 1,937	0
Debt instrument, weighted-average interest rate (as a percent)	4.30%
Maturing 2026-2028 | Japanese yen
Borrowings
Long-term debt, gross	$ 808	811
Debt instrument, weighted-average interest rate (as a percent)	1.50%
Maturing 2026-2027 | Other
Borrowings
Long-term debt, gross	$ 13	78
Debt instrument, weighted-average interest rate (as a percent)	13.40%
Finance Lease Obligations Maturing 2026-2035
Borrowings
Finance lease obligations	$ 1,240	$ 1,153
Finance lease obligations, interest rate (as a percent)	4.90%
2024 U.S. Dollar Fixed Rate Notes | U.S. dollar
Borrowings
Long-term debt, gross	$ 4,900