Fair Value Measurements, Recurring (Details) - Fair Value, Recurring [Member] - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022 |
Assets | | |
Investments in AFS debt securities | $ 224 | $ 221 |
Total gross fair value, assets | 919 | 1,133 |
Effect of counterparty netting | (425) | (705) |
Effect of cash collateral netting | (74) | (8) |
Net carrying value on Balance Sheet, assets | 420 | 420 |
Liabilities | | |
Blending program obligations | 46 | 55 |
Total gross fair value, liabilities | 485 | 766 |
Effect of counterparty netting | (425) | (705) |
Effect of cash collateral netting | 0 | 0 |
Net carrying value on Balance Sheet, liabilities | 60 | 61 |
Cash and Cash Equivalents [Member] | | |
Assets | | |
Investments in AFS debt securities | 98 | 125 |
Prepaid Expenses and Other [Member] | | |
Assets | | |
Investments in AFS debt securities | 126 | 96 |
Assets Held in Trust [Member] | | |
Assets | | |
Investments of certain benefit plans | 77 | 78 |
Commodity Contracts [Member] | | |
Assets | | |
Derivative contracts | 616 | 830 |
Effect of counterparty netting | (425) | (705) |
Effect of cash collateral netting | (74) | (8) |
Derivative contracts, net assets | 117 | 117 |
Cash collateral received not offset | 0 | 0 |
Liabilities | | |
Derivative contracts | 425 | 705 |
Effect of counterparty netting | (425) | (705) |
Effect of cash collateral netting | 0 | 0 |
Derivative contracts, net liabilities | 0 | 0 |
Cash collateral paid not offset | (1) | (149) |
Physical Purchase Contracts [Member] | | |
Assets | | |
Derivative contracts, not subject to netting | 2 | 4 |
Liabilities | | |
Derivative contracts, not subject to netting | 5 | 4 |
Foreign Currency Contracts [Member] | | |
Liabilities | | |
Derivative contracts, not subject to netting | 9 | 2 |
Fair Value, Inputs, Level 1 [Member] | | |
Assets | | |
Investments in AFS debt securities | 85 | 56 |
Total gross fair value, assets | 772 | 958 |
Liabilities | | |
Blending program obligations | 0 | 0 |
Total gross fair value, liabilities | 434 | 707 |
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] | | |
Assets | | |
Investments in AFS debt securities | 7 | 0 |
Fair Value, Inputs, Level 1 [Member] | Prepaid Expenses and Other [Member] | | |
Assets | | |
Investments in AFS debt securities | 78 | 56 |
Fair Value, Inputs, Level 1 [Member] | Assets Held in Trust [Member] | | |
Assets | | |
Investments of certain benefit plans | 71 | 72 |
Fair Value, Inputs, Level 1 [Member] | Commodity Contracts [Member] | | |
Assets | | |
Derivative contracts | 616 | 830 |
Liabilities | | |
Derivative contracts | 425 | 705 |
Fair Value, Inputs, Level 1 [Member] | Physical Purchase Contracts [Member] | | |
Assets | | |
Derivative contracts, not subject to netting | 0 | 0 |
Liabilities | | |
Derivative contracts, not subject to netting | 0 | 0 |
Fair Value, Inputs, Level 1 [Member] | Foreign Currency Contracts [Member] | | |
Liabilities | | |
Derivative contracts, not subject to netting | 9 | 2 |
Fair Value, Inputs, Level 2 [Member] | | |
Assets | | |
Investments in AFS debt securities | 139 | 165 |
Total gross fair value, assets | 141 | 169 |
Liabilities | | |
Blending program obligations | 46 | 55 |
Total gross fair value, liabilities | 51 | 59 |
Fair Value, Inputs, Level 2 [Member] | Cash and Cash Equivalents [Member] | | |
Assets | | |
Investments in AFS debt securities | 91 | 125 |
Fair Value, Inputs, Level 2 [Member] | Prepaid Expenses and Other [Member] | | |
Assets | | |
Investments in AFS debt securities | 48 | 40 |
Fair Value, Inputs, Level 2 [Member] | Assets Held in Trust [Member] | | |
Assets | | |
Investments of certain benefit plans | 0 | 0 |
Fair Value, Inputs, Level 2 [Member] | Commodity Contracts [Member] | | |
Assets | | |
Derivative contracts | 0 | 0 |
Liabilities | | |
Derivative contracts | 0 | 0 |
Fair Value, Inputs, Level 2 [Member] | Physical Purchase Contracts [Member] | | |
Assets | | |
Derivative contracts, not subject to netting | 2 | 4 |
Liabilities | | |
Derivative contracts, not subject to netting | 5 | 4 |
Fair Value, Inputs, Level 2 [Member] | Foreign Currency Contracts [Member] | | |
Liabilities | | |
Derivative contracts, not subject to netting | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | | |
Assets | | |
Investments in AFS debt securities | 0 | 0 |
Total gross fair value, assets | 6 | 6 |
Liabilities | | |
Blending program obligations | 0 | 0 |
Total gross fair value, liabilities | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | Assets Held in Trust [Member] | | |
Assets | | |
Investments of certain benefit plans | 6 | 6 |
Fair Value, Inputs, Level 3 [Member] | Commodity Contracts [Member] | | |
Assets | | |
Derivative contracts | 0 | 0 |
Liabilities | | |
Derivative contracts | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | Physical Purchase Contracts [Member] | | |
Assets | | |
Derivative contracts, not subject to netting | 0 | 0 |
Liabilities | | |
Derivative contracts, not subject to netting | 0 | 0 |
Fair Value, Inputs, Level 3 [Member] | Foreign Currency Contracts [Member] | | |
Liabilities | | |
Derivative contracts, not subject to netting | $ 0 | $ 0 |