INCOME TAXES - Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
IPR&D	$ (3,969)	$ (12,528)
Property and equipment	0	0
Total Deferred Tax Liabilities	$ (3,969)	$ (12,528)