EQUITY AWARD PLAN (Restricted Stock Units Activity) (Details) (RSU, USD $) Share data in Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
RSU
Number of Shares
Beginning balance (shares)	1,011
RSUs granted (shares)	2,289
RSUs exercised (shares)	(319)
RSUs forfeited (shares)	(156)
Ending balance (shares)	2,825	1,011
Weighted-Average Grant- Date Fair Value Per Share
RSUs outstanding (in dollars per share)	$ 13.65	$ 17.11
RSUs granted (in dollars per share)	$ 12.70	$ 17.10
RSUs vested (in dollars per share)	$ 17.53
RSUs forfeited (in dollars per share)	$ 14.27
RSU, Weighted Average Remaining Contractual Life	1 year 8 months 12 days	1 year 7 months 7 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value	$ 33,955,000	$ 14,356,000
Fair value of RSUs vested	$ 4,200,000

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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Number of non-option equity instruments exercised by participants.

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Net number of non-option equity instruments granted to participants.

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