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Fair Value Measurements - Recurring Narrative (Detail) | 3 Months Ended
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Mar. 31, 2018 USD ($)
Commodity derivatives | Level 3 | Minimum |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Forward commodity price | $ 0.26
Commodity derivatives | Level 3 | Maximum |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Forward commodity price | $ 1.47
Embedded derivatives in commodity contracts |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Embedded derivative renewal term | 5 years
Embedded derivatives in commodity contracts | Level 3 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Probability of renewal first term | 62.50%
Probability of renewal second term | 82.00%

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- Definition Represents the term for which the counterparty has the option to renew a purchase agreement related to an embedded derivative. + References No definition available. + Details
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- Definition Represents the forward commodity price used as an input to measure fair value. + References No definition available. + Details
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- Definition Represents the percentage of likelihood of renewal of the commodity contract with embedded derivative. + References No definition available. + Details
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- Definition Represents the percentage of likelihood of renewal of the commodity contract with embedded derivative for the second term of the contract. + References No definition available. + Details
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- Details
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