INCOME TAXES (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
INCOME TAXES
Federal income tax at 35% of earnings (loss) before income taxes	$ 31,739	$ 19,009	$ 29,972	$ 78,010
Federal income tax rate percentage (as a percent)			35.00%
State income taxes, net of federal income tax benefits	909	634	762	2,306
Change in valuation allowance for deferred tax assets	4,177	512	4,116	(178)
Canadian dividend tax, net of U.S. tax benefits	18,460		18,460
Initial public offering cost deductions	(2,660)		(2,660)
Effect of differing tax rates in Canada	(1,131)	175	(1,767)	(1,154)
Adjustments for statutory rate reductions and other	214	728	1,108	1,485
Total income tax	$ 51,708	$ 21,058	$ 49,991	$ 80,469

The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to statutory rate and other deductions received under enacted tax laws not otherwise listed in the existing taxonomy.

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Represents the Canadian tax levied on dividends, net of U.S. tax benefits.

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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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 portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to other deductions received under enacted tax laws not otherwise listed in the existing taxonomy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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