COMMITMENTS AND CONTINGENCIES - License Agreement (Details) - Innovative Cellular Therapeutics - USD ($)	May 10, 2017	May 09, 2017
Class of Stock [Line Items]
License agreement, initial payment	$ 6,000,000.0
License agreement, days within effective date of agreement initial payment due	60 days
License agreement, contingent consideration, asset	$ 8,000,000
License agreement, contingent consideration, liability	$ 5,000,000.0
Common Stock
Class of Stock [Line Items]
Warrants issued (in dollars per share)	$ 4.90	$ 3.05
Exercise price per share (in dollars per share)	$ 0.01