COMMITMENTS AND CONTINGENCIES, LEASES (Details) - Cambridge Lease $ in Thousands	Nov. 01, 2018 USD ($)	May 03, 2018 USD ($) ft²
Lessee, Lease, Description [Line Items]
Standby letter of credit \| $	$ 60	$ 40
Sublease
Lessee, Lease, Description [Line Items]
Lease space (in square feet) \| ft²		5,104

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration