Derivative Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2011

Derivative Financial Instruments (Tables) [Abstract]

Fair value of derivative instruments

	Asset Derivatives				Liability Derivatives
	September 30, 2011		December 31, 2010		September 30, 2011		December 31, 2010
Derivatives designated as hedging instruments:
Interest rate swaps	$	—	$	—	$	—	$	12,227
Natural gas swaps		—		22		345		248
Total derivatives designated as hedging instruments	$	—	$	22	$	345	$	12,475

Effect of derivative instruments on the statement of operations

	Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)							Amount Reclassified from Accumulated OCI into Income
Derivatives in Cash Flow Hedging Relationships	Three Months Ended September 30, 2011			Three Months Ended September 30, 2010			Location of Amount Reclassified from Accumulated OCI into Income	Three Months Ended September 30, 2011		Three Months Ended September 30, 2010
Interest rate swaps	$	1,529		$	3,100		Interest expense, net of amounts capitalized	$	—	$	—
Natural gas swaps		(125	)		(447	)	Other gains (losses), net		—		—
Total	$	1,404		$	2,653		Total	$	—	$	—

	Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)							Amount Reclassified from Accumulated OCI into Income
Derivatives in Cash Flow Hedging Relationships	Nine Months Ended September 30, 2011			Nine Months Ended September 30, 2010			Location of Amount Reclassified from Accumulated OCI into Income	Nine Months Ended September 30, 2011		Nine Months Ended September 30, 2010
Interest rate swaps	$	12,227		$	8,698		Interest expense, net of amounts capitalized	$	—	$	—
Natural gas swaps		(119	)		(540	)	Other gains (losses), net		—		(89	)
Total	$	12,108		$	8,158		Total	$	—	$	(89	)

		Amount of Gain Recognized in Income on Derivative
Derivatives Not Designated as Hedging Instruments	Location of Gain Recognized in Income on Derivatives	Three Months Ended September 30, 2011		Three Months Ended September 30, 2010		Nine Months Ended September 30, 2011		Nine Months Ended September 30, 2010
Natural gas swaps	Other gains and (losses), net	$	—	$	—	$	—	$	202