Consolidated Statements Of Comprehensive Income (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements Of Comprehensive Income [Abstract]
Net (loss) income	$ (3,782)	$ 96,849	$ 111,695	$ 175,845
Other comprehensive income (loss), before tax:
Gains (losses) on hedging instrument	141	(111)	310	(420)
Other comprehensive income (loss), before tax	141	(111)	310	(420)
Income tax expense (benefit) related to gains (losses) on hedging instrument	49	(39)	109	(147)
Comprehensive (loss) income, net of tax	$ (3,690)	$ 96,777	$ 111,896	$ 175,572

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Glossary Net Income

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+ Details

- Definition

Pre tax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, net of reclassifications into earnings during the period. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's increase or decrease in deferred hedging gains or losses. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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+ Details

- Definition

Pre-tax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, net of reclassifications into earnings during the period, attributable to the parent entity. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

+ References

+ Details