FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Cash and Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair value disclosure
Cash and cash equivalents	$ 64,108	$ 76,620
Short-term investments	37,024	48,339
Concentrations of Credit Risk of Financial Instruments
Cash, cash equivalents and short-term investments not FDIC-insured	32,300	42,600
Cash deposits
Fair value disclosure
Cash and cash equivalents	63,578	72,790
Variable rate demand notes
Fair value disclosure
Cash and cash equivalents	230	230
Money market funds
Fair value disclosure
Cash and cash equivalents	300	3,600
Certificates of deposit
Fair value disclosure
Short-term investments	$ 37,024	$ 48,339