FAIR VALUE MEASUREMENTS - Valuation of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Warrants issued to Foxconn
FAIR VALUE MEASUREMENTS
Derivative Liability	$ 300
Fair Value, Inputs, Level 3 | Private warrants to purchase common stock
FAIR VALUE MEASUREMENTS
Derivative Liability	23	$ 254
Fair Value, Inputs, Level 3 | Warrants issued to Foxconn
FAIR VALUE MEASUREMENTS
Derivative Liability	34	170
Fair Value, Recurring
FAIR VALUE MEASUREMENTS
Cash and Cash Equivalents	108,086	121,358
Short-term investments with a fair value	68,589	100,297
Fair Value, Recurring | Private warrants to purchase common stock
FAIR VALUE MEASUREMENTS
Derivative Liability	23	254
Fair Value, Recurring | Warrants issued to Foxconn
FAIR VALUE MEASUREMENTS
Derivative Liability	34
Fair Value, Recurring | Fair Value, Inputs, Level 1
FAIR VALUE MEASUREMENTS
Cash and Cash Equivalents	108,086	121,358
Fair Value, Recurring | Fair Value, Inputs, Level 2
FAIR VALUE MEASUREMENTS
Short-term investments with a fair value	68,589	100,297
Fair Value, Recurring | Fair Value, Inputs, Level 3 | Private warrants to purchase common stock
FAIR VALUE MEASUREMENTS
Derivative Liability	23	$ 254
Fair Value, Recurring | Fair Value, Inputs, Level 3 | Warrants issued to Foxconn
FAIR VALUE MEASUREMENTS
Derivative Liability	$ 34