DERIVATIVES AND RISK MANAGEMENT ACTIVITIES Table 2 - Derivative Instruments Eligible for Offset (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Commodity contracts
Derivative Assets and Liabilities Eligible for Offset, Net [Line Items]
Net amounts of liabilities presented in the consolidated balance sheets	$ (276)	$ (878)

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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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