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NET REVENUES FROM COLLABORATIONS - Schedule of Revenue Recognized by Accounting Guidance (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 05, 2024
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue Recognized	$ 659,825	$ 318,754	$ 1,154,158	$ 638,044
Roche \| Roche Collaboration and License Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	922,000		922,000
Revenue Recognized	12,797	0	84,948	0
Roche \| Roche License Obligation \| Roche Collaboration and License Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	375,000		375,000
Revenue Recognized	0	0	65,000	0
Roche \| Roche Development Services Obligation \| Roche Collaboration and License Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	545,000		545,000
Revenue Recognized	12,797	0	19,948	0
Roche \| Roche Technology Transfer Obligation \| Roche Collaboration and License Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	2,000		2,000
Revenue Recognized	0	0	0	0
Regeneron Pharmaceuticals \| Global Strategic Collaboration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	169,760		169,760		$ 329,686
Revenue Recognized	12,800	(13,900)	29,200	(1,000)
Regeneron Pharmaceuticals \| Research Services Obligation \| Global Strategic Collaboration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	102,969		102,969		75,469
Revenue Recognized	4,000	(17,000)	18,700	(6,300)
Regeneron Pharmaceuticals \| C5 License Obligation \| Global Strategic Collaboration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Transactional price remaining performance obligation	60,484		60,484		$ 56,390
Revenue Recognized	$ 8,800	$ 3,100	$ 10,500	$ 5,300