DISCONTINUED OPERATIONS - Discontinued Operations of the MST Franchise (Details) - Discontinued Operations, Disposed of by Sale - MST Franchise - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cost of goods sold	$ 80	$ 601
Research and development	0	2,078
Selling, general and administrative	(333)	10,884
Total operating expenses	(333)	12,962
Income (loss) from discontinued operations	359	(9,674)
Gain on the sale of the MST Franchise	13,005	0
Income (loss) from discontinued operations, before income taxes	13,364	(9,674)
Income tax expense	0	0
Net income (loss) from discontinued operations	13,364	(9,674)
Product sales
Total Revenues	$ 106	$ 3,889