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DEBT - Oxford Finance Loan and Security Agreement (Details) $ in Thousands					3 Months Ended		12 Months Ended
	Jul. 01, 2023	Dec. 27, 2022 USD ($)	May 21, 2022 USD ($) installment	May 04, 2021 USD ($) item	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)
Debt instruments
Effective interest rate					17.20%
Amount of principal outstanding					$ 33,957			$ 33,957
Interest expense					1,455	$ 1,474
Athyrium Credit Facility
Debt instruments
Amount of principal outstanding					33,957
Accretion of final prepayment fee					240	258
Interest expense					1,456	1,475
Amortization of debt discount					72	71
Contractual coupon interest					$ 1,144	$ 1,146
Athyrium
Debt instruments
Number of derivatives \| item				1
Athyrium \| Athyrium Credit Facility
Debt instruments
Additional interest rate upon an event of default accrued (as a percent)				5.00%
Loan Agreement
Debt instruments
Aggregate principal amount				$ 125,000
Floating interest rate (as a percent)				0.11%
Facility fees paid				$ 400
Percentage of final payment fees				7.00%
Debt repayments			$ 40,000
Partial prepayment			36,697
Amount of principal outstanding			80,000				$ 33,957
Prepayment fees paid			734
Final prepayment fee			$ 2,569
Number of monthly installments \| installment			5
Loss on extinguishment of debt							$ (2,583)
Loan Agreement \| Neither the tranche B term loan nor the tranche C term loan is made
Debt instruments
Duration of periodic monthly payment installments under a scenario				18 months
Loan Agreement \| Either tranche B term loan nor tranche C term loan is made
Debt instruments
Duration of periodic monthly payment installments under a scenario				12 months
Loan Agreement \| Payment on or before June 30, 2023
Debt instruments
Debt repayments		$ 5,000
Partial prepayment		4,673
Final prepayment fee		327
Loan Agreement \| Payment on or before January 31, 2024.
Debt instruments
Debt repayments		5,000
Partial prepayment		4,673
Final prepayment fee		327
Loan Agreement \| Payment on or prior to December 31, 2024
Debt instruments
Debt repayments		5,000
Loan Agreement \| Payment on or prior to June 30, 2025
Debt instruments
Debt repayments		$ 2,500
Loan Agreement \| Minimum
Debt instruments
Floating interest rate (as a percent)	8.00%
Loan Agreement \| 30-day LIBOR
Debt instruments
Spread on variable rate				7.89%
Loan Agreement \| 1- Month CME Term SOFR
Debt instruments
Floating interest rate (as a percent)	0.10%
Spread on variable rate	7.89%
Tranche A term loan
Debt instruments
Aggregate principal amount				$ 80,000
Tranche B term loan
Debt instruments
Facility fees paid				100
Tranche C term loan
Debt instruments
Facility fees paid				$ 125