DEVELOPMENT DERIVATIVE LIABILITY - Narrative (Details) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2023	Aug. 31, 2020	Jun. 30, 2024
Derivative [Line Items]
Cost of borrowing			11.00%
Blackstone Life Sciences
Derivative [Line Items]
Cost of borrowing			6.00%
Blackstone Life Sciences \| Development Milestone
Derivative [Line Items]
Development milestone, payable	$ 84.5
Net revenues from collaborations \| Blackstone Life Sciences \| Vutrisiran and ALN-AGT
Derivative [Line Items]
Maximum funding		$ 150.0
Net revenues from collaborations \| Blackstone Life Sciences \| HELIOS-B Phase 3 Clinical Trial
Derivative [Line Items]
Maximum funding		70.0
Net revenues from collaborations \| Blackstone Life Sciences \| ALN-AGT Phase 2 Clinical Trial
Derivative [Line Items]
Maximum funding		$ 26.0
Fixed payment multiplier		3.25
Fixed payment, term (in years)	4 years	4 years
Net revenues from collaborations \| Blackstone Life Sciences \| ALN-AGT Phase 3 Clinical Trial
Derivative [Line Items]
Maximum funding		$ 54.0
Fixed payment multiplier		4.5
Fixed payment, term (in years)		4 years
Net revenues from collaborations \| Blackstone Life Sciences \| Vutrisiran
Derivative [Line Items]
Royalties payable, percent		1.00%
Royalties payable, term (in years)		10 years
Fixed payment multiplier		2.5
Fixed payment, term (in years)		2 years