Derivative Financial Instruments and Fair Value Measurements - Derivatives Recorded at Fair Value in Consolidated Balance Sheets (Detail) - Not designated as hedging instruments - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 320	$ 2,416
Derivative Liabilities	2,266	12
Current | Commodities contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	320	2,416
Derivative Liabilities	$ 2,266	$ 12