LICENSE AGREEMENTS AND COMMITMENTS - Lease agreements (Details) $ in Thousands	1 Months Ended
	Feb. 28, 2019 USD ($) ft²	Feb. 28, 2018 USD ($)	Jan. 31, 2018 USD ($)
Laboratory, New Jersey
Leases
Leased area (in square feet) | ft²	4,500
Lease term	3 years
Option to extend	true
Option to extend, period	2 years
Fixed rent payable per annum	$ 144
Lease payable per month	$ 12
Corporate headquarters, New York
Leases
Lease term			5 years
Fixed rent payable per annum			$ 384
Lease payable per month			$ 32
Office space, Denmark
Leases
Lease term		3 years
Lease payable per month		$ 19