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Fair Value Measurements - Recurring Narrative (Detail) - USD ($) | 3 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Feb. 01, 2013
Fair Value, Measurements, Recurring |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Contingent consideration, liability |  |  | $ 131,000,000 | $ 130,000,000 |
Galveston Bay Refinery and Related Assets |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Maximum earnout payment, year four |  |  |  |  | $ 250,000,000
Maximum earnout payment, year five |  |  |  |  | 250,000,000
Maximum earnout payment, year six |  |  |  |  | 250,000,000
Total cumulative payment capped over six-year period |  |  |  |  | $ 700,000,000
Galveston Bay Refinery and Related Assets | Scenario, Forecast |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Contingent consideration payment |  | $ 131,000,000 |  |  |
Level 3 | Fair Value, Measurements, Recurring |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Contingent consideration, liability | [1] |  | 131,000,000 | 130,000,000 |
Level 1 | Fair Value, Measurements, Recurring |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Contingent consideration, liability |  |  | 0 | $ 0 |
Commodity derivatives | Level 3 | Ethanol prices | Minimum |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Forward commodity price |  |  | 0.24 |  |
Commodity derivatives | Level 3 | Ethanol prices | Maximum |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Forward commodity price |  |  | $ 1.16 |  |
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 |  |  | 50.00% |  |
Probability of renewal second term |  |  | 75.00% |  |
[1] | Includes $131 million and $130 million classified as current at March 31, 2017 and December 31, 2016, respectively.

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