ORGANIZATION, BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIIES - Percentage of Accounts Receivable (Details) - Accounts Receivable - Accounts receivable from collaboration agreements, cost reimbursements concentration risk	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Novartis Institutes for BioMedical Research, Inc.
Concentration Risk [Line Items]
Percentage of accounts receivable	59.00%	32.00%
Kite Pharma, Inc.
Concentration Risk [Line Items]
Percentage of accounts receivable	19.00%	2.00%
Biogen MA, Inc.
Concentration Risk [Line Items]
Percentage of accounts receivable	14.00%	46.00%
Sanofi S.A.
Concentration Risk [Line Items]
Percentage of accounts receivable	0.00%	11.00%