FINANCIAL INSTRUMENTS - Schedule of Investments at Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Measurements
Cost	$ 70,651	$ 516,845
Gross Unrealized Gains	182	350
Gross Unrealized Losses	(2)	(31)
Fair Value (Level 2)	70,831	517,164
Short-term:
Fair Value Measurements
Cost		421,416
Gross Unrealized Gains		320
Gross Unrealized Losses		(31)
Fair Value (Level 2)		421,705
Long-term:
Fair Value Measurements
Cost		95,429
Gross Unrealized Gains		30
Gross Unrealized Losses		0
Fair Value (Level 2)		95,459
Asset-backed securities \| Short-term:
Fair Value Measurements
Cost	3,182	34,918
Gross Unrealized Gains	0	98
Gross Unrealized Losses	0	0
Fair Value (Level 2)	3,182	35,016
Commercial paper \| Short-term:
Fair Value Measurements
Cost	57,533	221,494
Gross Unrealized Gains	80	36
Gross Unrealized Losses	(2)	(18)
Fair Value (Level 2)	57,611	221,512
Corporate bonds \| Short-term:
Fair Value Measurements
Cost	9,936	120,375
Gross Unrealized Gains	102	179
Gross Unrealized Losses	0	(11)
Fair Value (Level 2)	$ 10,038	120,543
U.S. Government bonds \| Short-term:
Fair Value Measurements
Cost		44,629
Gross Unrealized Gains		7
Gross Unrealized Losses		(2)
Fair Value (Level 2)		44,634
U.S. Government bonds \| Long-term:
Fair Value Measurements
Cost		95,429
Gross Unrealized Gains		30
Gross Unrealized Losses		0
Fair Value (Level 2)		$ 95,459

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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-Topic 320
-SubTopic 10
-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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Amortized cost excluding accrued interest, after allowance for credit loss, 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
-Topic 326
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Amount excluding accrued interest, 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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