Derivative Financial Instruments (Fair Value Of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Derivative financial instruments - Current assets	$ 39,499	$ 97,278
Derivative financial instruments - Long-term assets	6,109	2,138
Derivative financial instruments - Current liabilities	(16)	(892)
Derivative financial instruments - Long-term liabilities	0	0
Net derivative financial instruments	$ 45,592	$ 98,524

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 as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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