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STOCK BASED COMPENSATION - Non-vested Options Outstanding and Exercisable (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Stock options granted (in shares)	338	645
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value
Stock options granted (in dollars per share)	$ 2.99	$ 2.36	$ 0.49
Amended and Restated Equity Incentive Plan and Non-related Plan Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Balance at the beginning of the period (in shares)	2,463
Stock options granted (in shares)	392
Stock options cancelled/forfeited (in shares)	(19)
Stock options vested (in shares)	(1,357)
Balance at the end of the period (in shares)	1,479	2,463
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 1.08
Stock options granted (in dollars per share)	1.69
Stock options cancelled/forfeited (in dollars per share)	1.85
Stock options vested (in dollars per share)	1.08
Balance at the end of the period (in dollars per share)	$ 1.24	$ 1.08

X

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Number of non-vested options outstanding.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Number of non-vested options forfeited.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

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Number of options vested.

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Weighted average grant-date fair value of options vested.

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