INCOME TAXES - Schedule of Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating losses	$ 78,085	$ 81,471
Tax credit carryforwards	2,813	3,360
Stock-based compensation	2,770	2,999
Operating lease liabilities	545	1,248
Fixed assets	0	1,315
Reserves and other accruals not currently deductible	19,800	20,652
Disallowed interest carryforward	15,147	15,496
Total deferred tax assets	119,160	126,541
Valuation allowance for deferred tax assets	(101,775)	(103,906)
Deferred tax assets	17,385	22,635
Deferred tax liabilities:
Intangible assets	(16,812)	(21,739)
Convertible debt	(228)	(459)
Fixed Assets	(349)	0
Operating lease right-of-use assets	(168)	(437)
Net deferred tax liability	$ (172)	$ 0