Derivative Commodity Instruments (Tables)

3 Months Ended

Mar. 31, 2012

Derivative Commodity Instruments [Abstract]

Fair Values Of Derivative Instruments In Consolidated Balance Sheets

	Asset Derivatives
	Balance Sheet Location		Fair Value as of
			March 31, 2012		December 31, 2011
Designated as hedging instruments
Commodity forward contracts		Accounts receivable, net	$	5,729	$	—
Not designated as hedging instruments
Commodity forward contracts		Accounts receivable, net		1,442		2,437
Total asset derivatives			$	7,171	$	2,437
	Liability Derivatives
	Balance Sheet Location		Fair Value as of
			March 31, 2012		December 31, 2011
Designated as hedging instruments
Commodity forward contracts		Accrued liabilities	$	—	$	3,262
Not designated as hedging instruments
Commodity forward contracts		Accrued liabilities		939		973
Total liability derivatives			$	939	$	4,235

Impact Of Derivative Instruments Designated As Fair Value Hedges

Derivatives in Fair Value Hedging Relationships	Location of Gain  (Loss) Recognized in Income on Derivative	Three Months Ended March 31,
		2012		2011
Commodity forward contracts	Cost of sales	$	10,463	$	—

Hedged Items in Fair Value Hedging Relationships	Location of Gain  (Loss) Recognized in Income on Hedged Items	Three Months Ended March 31,
		2012			2011
Firm commitment designated as the hedged item	Cost of sales	$	(11,664	)	$	—

Impact Of Derivative Instruments Not Designated As Fair Value Hedges

Derivatives Not Designated as Hedging Instruments	Location of Gain  (Loss) Recognized in Income on Derivative	Three Months Ended March 31,
		2012		2011
Commodity forward contracts	Cost of sales	$	560	$	(16	)