STOCKHOLDERS' EQUITY (Schedule of Restricted Stock Units) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock Units (RSUs) [Member]
Restricted stock units, Number of Shares
Balance at the beginning of the period (in shares)	21,137	21,944	23,187
Stock units issued (in shares)	6,675	7,922	8,507
Stock units vested (in shares)	(7,943)	(7,271)	(7,975)
Stock units cancelled (in shares)	(1,696)	(2,084)	(1,783)
Balance at the end of the period (in shares)	18,163	21,137	21,944
Restricted stock units, Weighted Average Fair Value Per Share
Balance at the beginning of the period (in dollars per share)	$ 8.84	$ 8.71	$ 8.99
Restricted stock units issued (in dollars per share)	$ 8.44	$ 7.36	$ 6.11
Restricted stock units vested (in dollars per share)	$ 7.80	$ 7.30	$ 6.80
Restricted stock units cancelled (in dollars per share)	$ 7.93	$ 8.25	$ 7.81
Balance at the end of the period (in dollars per share)	$ 8.40	$ 8.84	$ 8.71
Performance-based Restricted Stock Units [Member]
Restricted stock units, Number of Shares
Stock units issued (in shares)		1,048	338
Stock units cancelled (in shares)		(422)	(330)
Restricted stock units, Weighted Average Fair Value Per Share
Restricted stock units issued (in dollars per share)		$ 7.33	$ 9.19
Restricted stock units cancelled (in dollars per share)		$ 13.50	$ 12.31
2014 Long-term Performance-based Incentive Plan [Member] \| Performance-based Restricted Stock Units [Member]
Restricted stock units, Number of Shares
Stock units issued (in shares)	26
Stock units cancelled (in shares)	(119)
Restricted stock units, Weighted Average Fair Value Per Share
Restricted stock units issued (in dollars per share)	$ 8.26
Restricted stock units cancelled (in dollars per share)	$ 7.31
2015 Long-term Performance-based Incentive Plan [Member] \| Performance-based Restricted Stock Units [Member]
Restricted stock units, Number of Shares
Stock units issued (in shares)	2,647
Restricted stock units, Weighted Average Fair Value Per Share
Restricted stock units issued (in dollars per share)	$ 7.67
2011 Long-term Performance-based Incentive Plan [Member] [Member] \| Performance-based Restricted Stock Units [Member]
Restricted stock units, Number of Shares
Stock units cancelled (in shares)	(2,564)
Restricted stock units, Weighted Average Fair Value Per Share
Restricted stock units cancelled (in dollars per share)	$ 13.58

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

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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.

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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).

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

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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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