FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value Assets
Marketable securities	$ 186,810	$ 0
Capped call transactions	71,716	0
Cash equivalents
Fair Value Assets
Cash equivalents	212,917	0
Venture investments
Fair Value Assets
Venture investments	7,927	4,871
Level 1
Fair Value Assets
Marketable securities	0	0
Capped call transactions	0	0
Level 1 \| Cash equivalents
Fair Value Assets
Cash equivalents	212,917	0
Level 1 \| Venture investments
Fair Value Assets
Venture investments	0	0
Level 2
Fair Value Assets
Marketable securities	186,810	0
Capped call transactions	71,716	0
Level 2 \| Cash equivalents
Fair Value Assets
Cash equivalents	0	0
Level 2 \| Venture investments
Fair Value Assets
Venture investments	0	0
Level 3
Fair Value Assets
Marketable securities	0	0
Capped call transactions	0	0
Level 3 \| Cash equivalents
Fair Value Assets
Cash equivalents	0	0
Level 3 \| Venture investments
Fair Value Assets
Venture investments	$ 7,927	$ 4,871

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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).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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.

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