CASH EQUIVALENTS, INVESTMENTS AND FAIR VALUE MEASUREMENTS - Available for sale debt securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Cash and Cash Equivalents [Line Items]
Short-term investments	$ 316,383	$ 426,181
Long-term investments		91,588
Total investments	409,557	579,018
Money market funds
Cash and Cash Equivalents [Line Items]
Cash equivalents	$ 93,174	$ 61,249

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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