STOCK-BASED COMPENSATION AND STOCK PLANS - Option activity (Details 1) - Stock Options	3 Months Ended
Mar. 31, 2016 $ / shares shares
Number of Shares
Outstanding as of December 31, 2015 \| shares	8,305,950
Granted \| shares	1,472,000
Exercised \| shares	(97,498)
Cancelled \| shares	(203,254)
Outstanding as of March 31, 2016 \| shares	9,477,198
Exercisable as of March 31, 2016 \| shares	6,383,542
Weighted Average Exercise Price
Outstanding as of December 31, 2014 \| $ / shares	$ 4.24
Granted \| $ / shares	1.79
Exercised \| $ / shares	1.16
Cancelled \| $ / shares	3.95
Outstanding as of March 31, 2016 \| $ / shares	3.89
Exercisable as of March 31, 2016 \| $ / shares	$ 4.93

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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