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FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financial assets:
Cash and cash equivalents	$ 136,627	$ 1,179,297
Level 1
Financial assets:
Cash and cash equivalents	136,627	1,179,297
Short-term investments	1,045,718
Restricted cash	6,882	1,860
Level 2
Financial assets:
Cash and cash equivalents	0	0
Short-term investments	0
Restricted cash	0	0
Level 3
Financial assets:
Cash and cash equivalents	0	0
Short-term investments	0
Restricted cash	0	0
Convertible Notes | Level 1
Financial liabilities:
Debt fair value	610,650	880,026
Convertible Notes | Level 2
Financial liabilities:
Debt fair value	0	0
Convertible Notes | Level 3
Financial liabilities:
Debt fair value	0	0
Offtake Advances | Level 1
Financial liabilities:
Debt fair value		0
Offtake Advances | Level 2
Financial liabilities:
Debt fair value		0
Offtake Advances | Level 3
Financial liabilities:
Debt fair value		16,501
Equipment notes | Level 1
Financial liabilities:
Debt fair value	0	0
Equipment notes | Level 2
Financial liabilities:
Debt fair value	6,807	9,737
Equipment notes | Level 3
Financial liabilities:
Debt fair value	0	0
Carrying Amount
Financial assets:
Cash and cash equivalents	136,627	1,179,297
Short-term investments	1,045,718
Restricted cash	6,882	1,860
Carrying Amount | Convertible Notes
Financial liabilities:
Debt fair value	678,444	674,927
Carrying Amount | Offtake Advances
Financial liabilities:
Debt fair value		16,082
Carrying Amount | Equipment notes
Financial liabilities:
Debt fair value	7,135	9,661
Fair Value
Financial assets:
Cash and cash equivalents	136,627	1,179,297
Short-term investments	1,045,718
Restricted cash	6,882	1,860
Fair Value | Convertible Notes
Financial liabilities:
Debt fair value	610,650	880,026
Fair Value | Offtake Advances
Financial liabilities:
Debt fair value		16,501
Fair Value | Equipment notes
Financial liabilities:
Debt fair value	$ 6,807	$ 9,737

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