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Fair Value Measurements Fair Value Measurements Using Significant Unobservable Inputs (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Sep. 30, 2021
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Commodity contract derivatives | $ 111 | $ 250
Commodity contract derivatives | 6 | 3
Fair Value, Inputs, Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Commodity contract derivatives | 0 | 0
Commodity contract derivatives | $ 0 | $ 0

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- Definition The fair value as of the balance sheet date of firm obligations in physical commodity contracts (for example, agricultural products, metals and energy). + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The fair value as of the balance sheet date of firm holdings in physical commodity contracts (for example, agricultural products, metals and energy). Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References No definition available. + Details
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- Details
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