RESTRUCTURING, COSTS BY CATEGORY (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Restructuring costs by category
Restructuring costs	$ 196
Research and development
Restructuring costs by category
Restructuring costs	139
General and administrative
Restructuring costs by category
Restructuring costs	$ 57

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Name:	us-gaap_RestructuringCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration