REVENUE RECOGNITION - Summary of Disaggregated Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Total revenue	$ 1,509	$ 331
Device
Disaggregation Of Revenue [Line Items]
Total revenue	1,192	169
Device | Point In Time
Disaggregation Of Revenue [Line Items]
Total revenue	1,192	169
Service
Disaggregation Of Revenue [Line Items]
Total revenue	317	162
Service | Over Time
Disaggregation Of Revenue [Line Items]
Total revenue	$ 317	$ 162