STOCKHOLDERS’ EQUITY Performance-Based Restricted Stock Units and Employee Stock Purchase Plan (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 13,687,000	$ 15,617,000
Purchase price of the entity's common stock expressed as percentage of fair market value at the commencement or end of the offering period	85.00%
Share Based Compensation, Arrangement by Share Based Payment Award, Offering Period	6 months
Performance-based Restricted Stock Unites (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
deferred compensation arrangement with individual performance based shares granted percentage	100.00%
Performance-based Restricted Stock Unites (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
deferred compensation arrangement with individual performance based shares granted percentage	200.00%
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of the rights to purchase shares (in dollars per share)	$ 0	$ 0
Cash proceeds from the issuance of shares	5,300,000	5,400,000
2015 Long-term Performance-based Incentive Plan [Member] \| Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued	(2,600,000)
2015 Long-term Performance-based Incentive Plan [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,300,000
2014 Long-term Performance-based Incentive Plan [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,000,000	1,100,000
Employee Stock Purchase Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of employee's eligible compensation as limitation on purchases	10.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount	$ 25,000
Shares purchased	800,000
Average purchase price per share	$ 6.97	$ 6.43
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	25,000,000
Number of shares available for issuances	18,200,000

deferred compensation arrangement with individual performance based shares granted percentage

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- Definition

Represents the average purchase price per share of shares purchased during the period under the employee stock purchase plan.

+ References

No definition available.

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- Definition

Represents the offering period with respect to which purchase price of the entity's common stock is determined under the Employee Stock Purchase Plan.

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Purchase price of the entity's common stock, expressed as a maximum percentage of fair market value of the common stock at a specified date, at which qualified employees are entitled to purchase shares under the Employee Stock Purchase Plan.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

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- Definition

The number of grants made 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).

+ References

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-Publisher FASB

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

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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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (a)(3)

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Topic 505

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-Section 02

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