EARNINGS PER SHARE - Reconciliation of weighted average shares outstanding (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
EARNINGS PER SHARE
Net (loss) income available for stockholders	$ (32,511)	$ 7,548
Less: Adjustments for earnings attributable to participating securities		(87)
Net (loss) income used in calculating earnings per share	$ (32,511)	$ 7,461
Weighted average shares outstanding (including participating securities)	217,433	213,492
Adjustment for participating securities	(3,322)	(3,423)
Shares used in calculating basic earnings per share	214,111	210,069
Dilutive effect of stock based awards		93
Shares used in calculating diluted earnings per share	214,111	210,162

Weighted number of shares including participating securties.

No definition available.

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- Definition

The total amount of dividends declared in the period for each class of stock and the contractual amount of dividends (or interest on participating income bonds) that must be paid for the period (for example, unpaid cumulative dividends). Dividends declared in the current period do not include dividends declared in respect of prior-period unpaid cumulative dividends. Preferred dividends that are cumulative only if earned are deducted only to the extent that they are earned.

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- Definition

This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

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

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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- 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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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.

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