FAIR VALUE MEASUREMENTS - Change in Investment in Privately Held Companies (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Convertible debt fair value	$ 573,000		$ 642,000
Privately held investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	7,648	$ 8,345
New investments	0	500
Sales of investments	0	(400)
Changes in foreign exchange rates	(61)	(9)
Changes in fair value included in other income	2,741	100
Changes in fair value included in other comprehensive income	2,502	1,220
Ending balance	$ 12,830	$ 9,756

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Changes in Foreign Exchange Rates

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Fair Value Adjustment Included in Other Comprehensive Income (Loss)

+ References

No definition available.

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Fair Value Adjustment Included in Other Income

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No definition available.

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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