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DEBT - Additional Information (Details) - Hercules and Silicon Valley Bank [Member] - USD ($) |  | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2022 | Sep. 30, 2020 | Dec. 31, 2023 | Sep. 15, 2023
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing capacity under term loan | $ 125,000,000 | $ 75,000,000 |  |
Principal amount outstanding under term loan |  |  | $ 80,000,000 |
Description of maturity date terms for term loan |  | Term Loan matures on April 1, 2025, or the Loan Maturity Date, and may be extended up to an additional six months upon the achievement of certain regulatory and financial milestones. |  |
Term loan interest rate description |  |  | The Term Loan bears interest at a floating rate per annum equal to the greater of either (i) 9.0% or (ii) the sum of (A) the Prime Rate (as reported in The Wall Street Journal) minus 4.5%, plus (B) 9.0% (8.5% as of December 31, 2023). |
Term loan maturity date |  | Apr. 01, 2025 |  |
Percentage added to prime rate for debt instrument interest rate |  | 9.00% |  |
Interest only period payment term description |  | The interest only period of the Term Loan is through June 30, 2024, and is further extendable to December 31, 2024 upon achievement of a regulatory and financial milestone and satisfaction of certain capitalization requirements. Following the expiration of the interest-only period, we are required to repay the Term Loan in equal monthly amortization payments of principal and interest until the Loan Maturity Date. |  |
End of term charge for loan, percentage |  | 6.55% |  |
Minimum amount of prepayment allowed under debt instrument |  | $ 5,000,000 |  |
Description of term loan payment terms |  | At our option, upon at least five business days’ prior written notice to Hercules, we may prepay all or any portion greater than or equal to $5.0 million of the outstanding loan by paying the entire principal balance (or portion thereof) and all accrued and unpaid interest. There is no prepayment charge for prepayments of drawdowns under Tranche 1 or Tranche 2. Prepayments of drawdowns under Tranche 3, Tranche 4, Tranche 5 or Tranche 6 are subject to a prepayment charge of 1.5% of the prepayment amount, if the prepayment is made prior to June 30, 2025. Thereafter, any prepayment of Tranche 3, Tranche 4, Tranche 5 or Tranche 6 is not subject to a prepayment charge. |  |
Variable interest rate |  | 9.00% |  |
Additional percentage of interest on past due amounts |  | 5.00% |  |
Carrying value of term loan, net |  |  | $ 81,900,000 |
Unamortized debt discount and issuance costs |  |  | 605,000 |
Accrued end of term charge |  |  | $ 2,691,000 |
Second Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt discount amount | 100,000 |  |  |
Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principal amount outstanding under term loan |  | $ 80,000,000 |  |
Percentage added to prime rate for debt instrument interest rate |  | 9.00% |  |
Debt discount amount | $ 300,000 |  |  |
Principle amount |  | $ 125,000,000 |  |
Variable interest rate |  | 9.00% |  |
Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 4.50% | 8.50% |
Minimum [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 4.50% |  |
Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 9.00% |  |
Maximum [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 9.00% |  |
Tranche One [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 0.00% |  |  |
Tranche Two [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 0.00% |  |  |
Tranche Three [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |
Debt instrument face amount expired |  |  |  | $ 20,000,000
Tranche Four [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |
Principle amount |  | $ 30,000,000 |  |
Tranche Four [Member] | Minimum [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principle amount |  | 10,000,000 |  |
Tranche Four [Member] | Maximum [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Principle amount |  | 30,000,000 |  |
Tranche Five [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |
Principle amount |  | $ 20,000,000 |  |
Tranche Six [Member] | Third Amendment [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |

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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
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- Details
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Balance Type: |
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- Details
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Balance Type: |
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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