DERIVATIVES (Fair Values Of Derivative Contracts) (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Derivatives, Fair Value [Line Items]
Gross fair value of assets	$ 30,422
Gross liabilities offset against assets in the Balance Sheet	(11,052)
Net fair value of assets presented in the Balance Sheet	19,370
Gross fair value of liabilities	12,942
Gross assets offset against liabilities in the Balance Sheet	(11,052)
Net fair value of liabilities presented in the Balance Sheet	1,890
Derivatives, current assets
Derivatives, Fair Value [Line Items]
Gross fair value of assets	22,512
Gross liabilities offset against assets in the Balance Sheet	(6,089)
Net fair value of assets presented in the Balance Sheet	16,423
Derivatives, long-term assets
Derivatives, Fair Value [Line Items]
Gross fair value of assets	7,910
Gross liabilities offset against assets in the Balance Sheet	(4,963)
Net fair value of assets presented in the Balance Sheet	2,947
Derivatives, current liabilities
Derivatives, Fair Value [Line Items]
Gross fair value of liabilities	7,799
Gross assets offset against liabilities in the Balance Sheet	(6,089)
Net fair value of liabilities presented in the Balance Sheet	1,710
Derivatives, long-term liabilities
Derivatives, Fair Value [Line Items]
Gross fair value of liabilities	5,143
Gross assets offset against liabilities in the Balance Sheet	(4,963)
Net fair value of liabilities presented in the Balance Sheet	$ 180

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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