FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets:
Cash and cash equivalents	$ 284,434	$ 263,351
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	284,434	263,351
Short-term investments	582,056	734,493
Restricted cash	1,160	1,637
Fair Value, Inputs, Level 1 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2026
Financial liabilities:
Debt fair value	192,938	619,496
Fair Value, Inputs, Level 1 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2030
Financial liabilities:
Debt fair value	823,812
Fair Value, Inputs, Level 1 [Member] \| Equipment notes
Financial liabilities:
Debt fair value	0	0
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents	0	0
Short-term investments	0	0
Restricted cash	0	0
Fair Value, Inputs, Level 2 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2026
Financial liabilities:
Debt fair value	0	0
Fair Value, Inputs, Level 2 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2030
Financial liabilities:
Debt fair value	0
Fair Value, Inputs, Level 2 [Member] \| Equipment notes
Financial liabilities:
Debt fair value	3,114	4,628
Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents	0	0
Short-term investments	0	0
Restricted cash	0	0
Fair Value, Inputs, Level 3 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2026
Financial liabilities:
Debt fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Convertible Debt [Member] \| Convertible Notes due 2030
Financial liabilities:
Debt fair value	0
Fair Value, Inputs, Level 3 [Member] \| Equipment notes
Financial liabilities:
Debt fair value	0	0
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	284,434	263,351
Short-term investments	582,056	734,493
Restricted cash	1,160	1,637
Reported Value Measurement [Member] \| Convertible Debt [Member] \| Convertible Notes due 2026
Financial liabilities:
Debt fair value	208,362	681,980
Reported Value Measurement [Member] \| Convertible Debt [Member] \| Convertible Notes due 2030
Financial liabilities:
Debt fair value	729,272
Reported Value Measurement [Member] \| Equipment notes
Financial liabilities:
Debt fair value	3,147	4,743
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	284,434	263,351
Short-term investments	582,056	734,493
Restricted cash	1,160	1,637
Estimate of Fair Value Measurement [Member] \| Convertible Debt [Member] \| Convertible Notes due 2026
Financial liabilities:
Debt fair value	192,938	619,496
Estimate of Fair Value Measurement [Member] \| Convertible Debt [Member] \| Convertible Notes due 2030
Financial liabilities:
Debt fair value	823,812
Estimate of Fair Value Measurement [Member] \| Equipment notes
Financial liabilities:
Debt fair value	$ 3,114	$ 4,628

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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