(LOSS) EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings per share calculation
Net (loss) income	$ (116,025)	$ 159,559	$ (208,193)
Basic weighted-average number of common shares outstanding (000s)	305,446	304,655	195,808
Diluted effect of stock options and RSUs (000s)		8,484
Diluted effect of convertible notes (000s)		12,980
Diluted weighted-average number of common shares outstanding (000s)	305,446	326,119	195,808
Basic (loss) earnings per share (in dollars per share)	$ (0.38)	$ 0.52	$ (1.06)
Diluted (loss) earnings per share (in dollars per share)	$ (0.38)	$ 0.49	$ (1.06)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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+ Details