SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Total revenues	$ 10,084	$ 15,878	$ 32,791	$ 46,102
Intellectual property operations
Disaggregation of Revenue [Line Items]
Total revenues	1,760	6,320	6,330	16,997
Paid-up license revenue agreements
Disaggregation of Revenue [Line Items]
Total revenues	1,410	6,000	5,385	15,553
Recurring License Revenue Agreements
Disaggregation of Revenue [Line Items]
Total revenues	350	320	945	1,444
Industrial operations
Disaggregation of Revenue [Line Items]
Total revenues	8,324	9,558	26,461	29,105
Printers, consumables and parts
Disaggregation of Revenue [Line Items]
Total revenues	7,428	8,509	23,714	26,023
Services
Disaggregation of Revenue [Line Items]
Total revenues	$ 896	$ 1,049	$ 2,747	$ 3,082