Fair Value Measurement - Fair Value Measurement Inputs (Details) - USD ($) $ in Millions | Jun. 30, 2022 | Dec. 31, 2021 |
Investment securities (current and long-term): | | |
Marketable Securities | $ 0 | |
Other Assets, Current | 608 | $ 523 |
Other assets | 1,501 | 1,460 |
Derivatives: | | |
Derivative Asset | 49 | 73 |
Derivatives: [Abstract] | | |
Derivative Liability | 542 | 24 |
Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 26 | 29 |
Trust Assets Fair Value Disclosure | 56 | 64 |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Discontinued Operation, Contingent Receivable | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Long-term debt, including current portion | 0 | 0 |
Level 1 | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 5 | 50 |
Trust Assets Fair Value Disclosure | 8 | 8 |
Derivatives: | | |
Derivative Asset | 8 | 10 |
Discontinued Operation, Contingent Receivable | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 64 | 1 |
Long-term debt, including current portion | 0 | 0 |
Level 2 | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 0 | 0 |
Trust Assets Fair Value Disclosure | 122 | 137 |
Derivatives: | | |
Derivative Asset | 45 | 67 |
Discontinued Operation, Contingent Receivable | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 482 | 27 |
Long-term debt, including current portion | 10,601 | 10,630 |
Level 3 | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 0 | 0 |
Trust Assets Fair Value Disclosure | 0 | 0 |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Discontinued Operation, Contingent Receivable | 67 | 81 |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Long-term debt, including current portion | 0 | 0 |
Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 31 | 79 |
Trust Assets Fair Value Disclosure | 186 | 209 |
Derivatives: | | |
Derivative Asset | 53 | 77 |
Discontinued Operation, Contingent Receivable | 67 | 81 |
Derivatives: [Abstract] | | |
Derivative Liability | 546 | 28 |
Long-term debt, including current portion | 10,601 | 10,630 |
Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Investments, Fair Value Disclosure | 31 | 79 |
Trust Assets Fair Value Disclosure | 186 | 209 |
Derivatives: | | |
Derivative Asset | 53 | 77 |
Discontinued Operation, Contingent Receivable | 79 | 90 |
Derivatives: [Abstract] | | |
Derivative Liability | 546 | 28 |
Long-term debt, including current portion | 11,092 | 9,450 |
Embedded Derivative Financial Instruments | | |
Derivatives: | | |
Derivative Asset | 38 | 61 |
Derivatives: [Abstract] | | |
Derivative Liability | 476 | 24 |
Embedded Derivative Financial Instruments | Fair Value Measured at Net Asset Value Per Share | | |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Embedded Derivative Financial Instruments | Level 1 | | |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Embedded Derivative Financial Instruments | Level 2 | | |
Derivatives: | | |
Derivative Asset | 38 | 64 |
Derivatives: [Abstract] | | |
Derivative Liability | 476 | 27 |
Embedded Derivative Financial Instruments | Level 3 | | |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Embedded Derivative Financial Instruments | Estimate of Fair Value Measurement | | |
Derivatives: | | |
Derivative Asset | 38 | 64 |
Derivatives: [Abstract] | | |
Derivative Liability | 476 | 27 |
Embedded Derivative Financial Instruments | Carrying Amount, Fair Value Disclosure | | |
Derivatives: | | |
Derivative Asset | 38 | 64 |
Derivatives: [Abstract] | | |
Derivative Liability | 476 | 27 |
Forward Contracts | Level 1 | | |
Derivatives: | | |
Derivative Asset | 8 | 1 |
Forward Contracts | Level 2 | | |
Derivatives: | | |
Derivative Asset | 7 | 0 |
Forward Contracts | Level 3 | | |
Derivatives: | | |
Derivative Asset | 0 | 0 |
Forward Contracts | Estimate of Fair Value Measurement | | |
Derivatives: | | |
Derivative Asset | 15 | 1 |
Forward Contracts | Carrying Amount, Fair Value Disclosure | | |
Derivatives: | | |
Derivative Asset | 15 | 1 |
Commodity Contract | | |
Derivatives: | | |
Derivative Asset | 11 | 12 |
Derivatives: [Abstract] | | |
Derivative Liability | 66 | 0 |
Commodity Contract | Fair Value Measured at Net Asset Value Per Share | | |
Derivatives: | | |
Derivative Asset | | 0 |
Commodity Contract | Fair Value Measured at Net Asset Value Per Share | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Commodity Contract | Fair Value Measured at Net Asset Value Per Share | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | |
Commodity Contract | Level 1 | | |
Derivatives: | | |
Derivative Asset | | 9 |
Commodity Contract | Level 1 | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 3 | 1 |
Commodity Contract | Level 1 | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 61 | |
Commodity Contract | Level 2 | | |
Derivatives: | | |
Derivative Asset | | 3 |
Commodity Contract | Level 2 | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 1 | 0 |
Commodity Contract | Level 2 | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 5 | |
Commodity Contract | Level 3 | | |
Derivatives: | | |
Derivative Asset | | 0 |
Commodity Contract | Level 3 | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | 0 |
Commodity Contract | Level 3 | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 0 | |
Commodity Contract | Estimate of Fair Value Measurement | | |
Derivatives: | | |
Derivative Asset | | 12 |
Commodity Contract | Estimate of Fair Value Measurement | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 4 | 1 |
Commodity Contract | Estimate of Fair Value Measurement | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 66 | |
Commodity Contract | Carrying Amount, Fair Value Disclosure | | |
Derivatives: | | |
Derivative Asset | | 12 |
Commodity Contract | Carrying Amount, Fair Value Disclosure | Forward Contracts | | |
Derivatives: [Abstract] | | |
Derivative Liability | 4 | 1 |
Commodity Contract | Carrying Amount, Fair Value Disclosure | Futures and Swaps | | |
Derivatives: [Abstract] | | |
Derivative Liability | 66 | |
U.S. core fixed income fund | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Marketable Securities | 26 | 29 |
Trust Assets Fair Value Disclosure | 56 | 64 |
U.S. core fixed income fund | Level 1 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 0 | 0 |
Trust Assets Fair Value Disclosure | 0 | 0 |
U.S. core fixed income fund | Level 2 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 0 | 0 |
Trust Assets Fair Value Disclosure | 0 | 0 |
U.S. core fixed income fund | Level 3 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 0 | 0 |
Trust Assets Fair Value Disclosure | 0 | 0 |
U.S. core fixed income fund | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Marketable Securities | 26 | 29 |
Trust Assets Fair Value Disclosure | 56 | 64 |
U.S. core fixed income fund | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Marketable Securities | 26 | 29 |
Trust Assets Fair Value Disclosure | 56 | 64 |
Equity securities | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Marketable Securities | | 0 |
Equity securities | Level 1 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 5 | 50 |
Equity securities | Level 2 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 0 | 0 |
Equity securities | Level 3 | | |
Investment securities (current and long-term): | | |
Marketable Securities | 0 | 0 |
Equity securities | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Marketable Securities | 5 | 50 |
Equity securities | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Marketable Securities | 5 | 50 |
Government bonds | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government bonds | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government bonds | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 39 | 53 |
Government bonds | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government bonds | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 39 | 53 |
Government bonds | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 39 | 53 |
Corporate bonds | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Corporate bonds | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Corporate bonds | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 36 | 45 |
Corporate bonds | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Corporate bonds | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 36 | 45 |
Corporate bonds | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 36 | 45 |
Government mortgage-backed securities | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government mortgage-backed securities | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government mortgage-backed securities | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 28 | 20 |
Government mortgage-backed securities | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Government mortgage-backed securities | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 28 | 20 |
Government mortgage-backed securities | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 28 | 20 |
Asset-backed securities | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Asset-backed securities | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Asset-backed securities | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 16 | 18 |
Asset-backed securities | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Asset-backed securities | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 16 | 18 |
Asset-backed securities | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 16 | 18 |
Money market funds | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Money market funds | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 8 | 8 |
Money market funds | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Money market funds | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | 0 |
Money market funds | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 8 | 8 |
Money market funds | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 8 | 8 |
Collateralized Mortgage Backed Securities | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | |
Collateralized Mortgage Backed Securities | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | |
Collateralized Mortgage Backed Securities | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 3 | |
Collateralized Mortgage Backed Securities | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 0 | |
Collateralized Mortgage Backed Securities | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 3 | |
Collateralized Mortgage Backed Securities | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | 3 | |
Municipal bonds | Fair Value Measured at Net Asset Value Per Share | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 0 |
Municipal bonds | Level 1 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 0 |
Municipal bonds | Level 2 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 1 |
Municipal bonds | Level 3 | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 0 |
Municipal bonds | Estimate of Fair Value Measurement | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 1 |
Municipal bonds | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Trust Assets Fair Value Disclosure | | 1 |
Bank Time Deposits | Carrying Amount, Fair Value Disclosure | | |
Investment securities (current and long-term): | | |
Other Assets, Current | 119 | 114 |
Other assets | 134 | 132 |
Fair Value, Recurring [Member] | Forward Contracts | Estimate of Fair Value Measurement | | |
Derivatives: | | |
Derivative Asset | $ 0 | $ 0 |