FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value Assets:
Marketable securities	$ 293,269	$ 0
Capped Call Transactions	83,597	0
Level 1
Fair Value Assets:
Marketable securities	0	0
Capped Call Transactions	0	0
Level 2
Fair Value Assets:
Marketable securities	293,269	0
Capped Call Transactions	83,597	0
Level 3
Fair Value Assets:
Marketable securities	0	0
Capped Call Transactions	0	0
Cash Equivalents
Fair Value Assets:
Cash equivalents	56,339	0
Cash Equivalents \| Level 1
Fair Value Assets:
Cash equivalents	42,339	0
Cash Equivalents \| Level 2
Fair Value Assets:
Cash equivalents	14,000	0
Cash Equivalents \| Level 3
Fair Value Assets:
Cash equivalents	0	0
Venture investments
Fair Value Assets:
Venture investments	8,345	4,871
Venture investments \| Level 1
Fair Value Assets:
Venture investments	0	0
Venture investments \| Level 2
Fair Value Assets:
Venture investments	0	0
Venture investments \| Level 3
Fair Value Assets:
Venture investments	$ 8,345	$ 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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- Definition

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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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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