Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions | Sep. 30, 2022 | May 31, 2022 | Dec. 31, 2021 |
Debt Instrument [Line Items] | | | |
Long-term and short-term, combined amount, gross | $ 16,206 | | $ 17,766 |
Finance leases | 1,282 | | 1,261 |
Net unamortized premiums, discounts and debt issuance costs | (527) | | 907 |
Total debt | 16,961 | | 19,934 |
Short-term debt | (664) | | (1,200) |
Long-term debt | $ 16,297 | | 18,734 |
2.4% Notes due 2022 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.40% | | |
Long-term and short-term, combined amount, gross | $ 329 | | 329 |
7.65% Debentures due 2023 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.65% | | |
Long-term and short-term, combined amount, gross | $ 78 | | 78 |
3.35% Notes due 2024 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 3.35% | | |
Long-term and short-term, combined amount, gross | $ 426 | | 426 |
2.125% Notes due 2024 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.125% | | |
Long-term and short-term, combined amount, gross | $ 900 | | 0 |
8.2% Notes due 2025 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 8.20% | | |
Long-term and short-term, combined amount, gross | $ 134 | | 134 |
3.35% Debentures due 2025 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 3.35% | | |
Long-term and short-term, combined amount, gross | $ 199 | | 199 |
2.4% Notes due 2025 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.40% | | |
Long-term and short-term, combined amount, gross | $ 900 | | 0 |
6.875% Debentures due 2026 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 6.875% | | |
Long-term and short-term, combined amount, gross | $ 67 | | 67 |
4.95% Notes due 2026 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.95% | 4.95% | |
Long-term and short-term, combined amount, gross | $ 0 | | 1,250 |
7.8% Debentures due 2027 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.80% | | |
Long-term and short-term, combined amount, gross | $ 203 | | 203 |
3.75% Notes due 2027 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 3.75% | | |
Long-term and short-term, combined amount, gross | $ 196 | | 1,000 |
4.3% Notes due 2028 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.30% | | |
Long-term and short-term, combined amount, gross | $ 223 | | 1,000 |
7.375% Debentures due 2029 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.375% | | |
Long-term and short-term, combined amount, gross | $ 92 | | 92 |
7% Debentures due 2029 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7% | | |
Long-term and short-term, combined amount, gross | $ 112 | | 200 |
6.95% Notes due 2029 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 6.95% | | |
Long-term and short-term, combined amount, gross | $ 1,195 | | 1,549 |
8.125% Notes due 2030 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 8.125% | | |
Long-term and short-term, combined amount, gross | $ 390 | | 390 |
7.4% Notes due 2031 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.40% | | |
Long-term and short-term, combined amount, gross | $ 382 | | 500 |
7.25% Notes due 2031 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.25% | | |
Long-term and short-term, combined amount, gross | $ 400 | | 500 |
7.2% Notes due 2031 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.20% | | |
Long-term and short-term, combined amount, gross | $ 447 | | 575 |
2.4% Notes due 2031 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.40% | | |
Long-term and short-term, combined amount, gross | $ 227 | | 500 |
5.9% Notes due 2032 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 5.90% | | |
Long-term and short-term, combined amount, gross | $ 505 | | 505 |
4.15% Notes due 2034 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.15% | | |
Long-term and short-term, combined amount, gross | $ 246 | | 246 |
5.95% Notes due 2036 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 5.95% | | |
Long-term and short-term, combined amount, gross | $ 326 | | 500 |
5.951% Notes due 2037 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 5.951% | | |
Long-term and short-term, combined amount, gross | $ 645 | | 645 |
5.9% Notes due 2038 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 5.90% | | |
Long-term and short-term, combined amount, gross | $ 350 | | 600 |
6.5% Notes due 2039 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 6.50% | | |
Long-term and short-term, combined amount, gross | $ 1,588 | | 2,750 |
3.758% Notes due 2042 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 3.758% | | |
Long-term and short-term, combined amount, gross | $ 785 | | 0 |
4.3% Notes due 2044 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.30% | | |
Long-term and short-term, combined amount, gross | $ 750 | | 750 |
5.95% Notes due 2046 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 5.95% | | |
Long-term and short-term, combined amount, gross | $ 329 | | 500 |
7.9% Debentures due 2047 | Debentures | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 7.90% | | |
Long-term and short-term, combined amount, gross | $ 60 | | 60 |
4.875% Notes due 2047 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.875% | | |
Long-term and short-term, combined amount, gross | $ 319 | | 800 |
4.85% Notes due 2048 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.85% | | |
Long-term and short-term, combined amount, gross | $ 219 | | 600 |
3.8% Notes due 2052 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 3.80% | | |
Long-term and short-term, combined amount, gross | $ 1,100 | | 0 |
4.025% Notes due 2062 | Notes Payable to Banks | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 4.025% | | |
Long-term and short-term, combined amount, gross | $ 1,770 | | 0 |
Floating rate notes due 2022 at 1.06% – 1.41% during 2022 and 1.02% –1.12% during 2021 | Floating Rate Notes | | | |
Debt Instrument [Line Items] | | | |
Long-term and short-term, combined amount, gross | $ 0 | | $ 500 |
Floating rate notes due 2022 at 1.06% – 1.41% during 2022 and 1.02% –1.12% during 2021 | Floating Rate Notes | Minimum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 1.06% | | 1.02% |
Floating rate notes due 2022 at 1.06% – 1.41% during 2022 and 1.02% –1.12% during 2021 | Floating Rate Notes | Maximum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 1.41% | | 1.12% |
Marine Terminal Revenue Refunding Bonds due 2031 at 0.07% – 2.55% during 2022 and 0.04% – 0.15% during 2021 | Variable Rate Debt Bonds | | | |
Debt Instrument [Line Items] | | | |
Long-term and short-term, combined amount, gross | $ 265 | | $ 265 |
Marine Terminal Revenue Refunding Bonds due 2031 at 0.07% – 2.55% during 2022 and 0.04% – 0.15% during 2021 | Variable Rate Debt Bonds | Minimum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 0.07% | | 0.04% |
Marine Terminal Revenue Refunding Bonds due 2031 at 0.07% – 2.55% during 2022 and 0.04% – 0.15% during 2021 | Variable Rate Debt Bonds | Maximum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.55% | | 0.15% |
Industrial Development Bonds due 2035 at 0.07% – 2.55% during 2022 and 0.04% – 0.12% during 2021 | Variable Rate Debt Bonds | | | |
Debt Instrument [Line Items] | | | |
Long-term and short-term, combined amount, gross | $ 18 | | $ 18 |
Industrial Development Bonds due 2035 at 0.07% – 2.55% during 2022 and 0.04% – 0.12% during 2021 | Variable Rate Debt Bonds | Minimum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 0.07% | | 0.04% |
Industrial Development Bonds due 2035 at 0.07% – 2.55% during 2022 and 0.04% – 0.12% during 2021 | Variable Rate Debt Bonds | Maximum | | | |
Debt Instrument [Line Items] | | | |
Stated interest rate | 2.55% | | 0.12% |
Other | | | |
Debt Instrument [Line Items] | | | |
Long-term and short-term, combined amount, gross | $ 31 | | $ 35 |