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Derivative Instruments - Balance Sheet Location (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Foreign currency derivatives | Not Designated as Hedging Instrument | Prepaid and other current assets
Derivatives, Fair Value
Derivative asset fair value	$ 67	$ 0
Foreign currency derivatives | Not Designated as Hedging Instrument | Other current liabilities
Derivatives, Fair Value
Derivative liability fair value	80	43
Cash Flow Hedging | Commodity derivative contracts | Designated as Hedging Instrument
Derivatives, Fair Value
Derivative asset fair value	20,516	350
Derivative liability fair value	1	11,023
Cash Flow Hedging | Commodity derivative contracts | Designated as Hedging Instrument | Prepaid and other current assets
Derivatives, Fair Value
Derivative asset fair value	9,035	90
Cash Flow Hedging | Commodity derivative contracts | Designated as Hedging Instrument | Other accrued liabilities
Derivatives, Fair Value
Derivative liability fair value	1	4,630
Cash Flow Hedging | Commodity derivative contracts | Designated as Hedging Instrument | Other long-term assets
Derivatives, Fair Value
Derivative asset fair value	11,481	260
Cash Flow Hedging | Commodity derivative contracts | Designated as Hedging Instrument | Other long-term obligations
Derivatives, Fair Value
Derivative liability fair value	$ 0	$ 6,393

X

- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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