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Derivative Financial Instruments and Fair Value Measurements - Summary of Derivative Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Commodities contracts - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Derivatives, Fair Value [Line Items]    
Asset, Fair Value $ 320 $ 2,416
Liability, Fair Value 2,266 12
Level 1    
Derivatives, Fair Value [Line Items]    
Asset, Fair Value 0 0
Liability, Fair Value 0 0
Level 2    
Derivatives, Fair Value [Line Items]    
Asset, Fair Value 320 2,416
Liability, Fair Value 2,266 12
Level 3    
Derivatives, Fair Value [Line Items]    
Asset, Fair Value 0 0
Liability, Fair Value $ 0 $ 0