Commodity Risk Derivatives - Schedule of Fair Value Commodity Derivatives (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Price Risk Derivatives [Abstract]
Fair value of oil and natural gas derivatives - Current Assets, Gross Amount	$ 4	$ 168
Fair value of oil and natural gas derivatives - Current Assets, Amount Offset	(4)	(168)
Fair value of oil and natural gas derivatives - Current Assets
Fair value of oil and natural gas derivatives - Current Liabilities, Gross Amount	(41)	(329)
Fair value of oil and natural gas derivatives - Current Liabilities, Amount Offset	4	168
Fair value of oil and natural gas derivatives - Current Liabilities	$ (37)	$ (161)

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value of liability associated with 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.

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Fair value, after the 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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Fair value of asset associated with financial liability or 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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No definition available.

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