Condensed Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Condensed Consolidated Statement of Comprehensive Income [Abstract]
Net income	$ 50,974	$ 39,792
Other comprehensive (loss), net of tax effect:
Adjustment for fair value accounting of derivatives	(22,065)	(32,474)
Comprehensive income	$ 28,909	$ 7,318

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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-Publisher FASB

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-Name Accounting Standards Codification

-Glossary Comprehensive Income

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-Name Accounting Standards Codification

-Glossary Net Income

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-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

+ Details

- Definition

This element represents the income or loss from continuing operations attributable to the parent which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any.

+ References

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+ Details

- Definition

Net of tax effect change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges after taxes. 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. The change 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