v2.4.0.6

Derivative Commodity Instruments (Fair Values Of Derivative Instruments In Consolidated Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Derivative [Line Items]
Total asset derivatives	$ 2,437	$ 47
Total liability derivatives	4,235	46
Accounts Receivable, Net [Member] | Commodity Forward Contracts [Member]
Derivative [Line Items]
Derivatives Not Designated as Hedging Instruments, Asset Derivatives	2,437	47
Accrued Liabilities [Member] | Commodity Forward Contracts [Member]
Derivative [Line Items]
Derivatives Designated as Hedging Instruments, Liability Derivatives	3,262
Derivatives Not Designated as Hedging Instruments, Liability Derivatives	$ 973	$ 46

X

- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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