OTHER FINANCIAL INFORMATION - Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jul. 19, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued sales and other taxes	$ 5,213	$ 5,752
Accrued professional fees	5,912	4,367
Accrued dividends on Redeemable Series A Preferred Stock	3,842	3,889
Current maturities of capital lease obligations	429	222	$ 6,400
Income taxes payable	2,245	1,091
Appeal proceeds payable to insurance company	0	4,388
Other accrued expenses	3,513	3,638
Total other accrued liabilities	$ 21,154	$ 23,347