INCOME TAXES (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
INCOME TAXES
Tax expense	$ 20,515	$ 16,191	$ 58,582	$ 44,431
Pre-tax income	75,873	48,819	217,904	135,132
Effective income tax rate (as a percent)			26.90%	32.90%
Tax benefit for tax audit settlements			4,844
Unrecognized tax benefits	28,797		28,797
Unrecognized tax benefits that, if recognized, would be recognized as a component of income tax expense	18,251		18,251
Reasonably possible reduction in prior years' unrecognized tax benefits during the next twelve months	$ 7,059		$ 7,059

Reflects the effects of adjustments of previously recorded tax expense, interest, and/or penalties for significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversals and tax settlements.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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