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DEBT - Additional Information (Details) - USD ($) |  | 6 Months Ended |
--- | --- | --- | ---
Jun. 01, 2022 | Jun. 30, 2022 | Sep. 30, 2020
Debt Instrument [Line Items] |  |  |
Unamortized debt discount and issuance costs |  | $ 801,000 |
Hercules and Silicon Valley Bank [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity under term loan |  | 125,000,000 | $ 75,000,000
Principal amount outstanding under term loan |  | 50,000,000 |
Carrying value of term loan, net |  | 50,420,000 |
Unamortized debt discount and issuance costs |  | 801,000 |
Accrued end of term charge |  | 1,221,000 |
Hercules and Silicon Valley Bank [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Available remaining loan principal under second amendment |  | 75,000,000 |
Debt discount under second amendment |  | 100,000 |
Debt issuance costs |  | $ 14,000 |
Prepayment charge (as a percentage) |  | 1.50% |
Charge for prepayment occurring 36 months after effective date |  | $ 0 |
Description of term loan payment terms |  | Under the second amendment, if we choose to prepay the principal with respect to any future draw down after the Effective Date, any such prepayment within the first 36 months after the Effective Date will be subject to a prepayment charge equal to 1.5% of the principal amount prepaid. No prepayment charge will be assessed for any prepayment occurring more than 36 months after the Effective Date. |
Minimum cash balance as a percentage of loan amount outstanding | 50.00% |  |
Debt covenant minimum cash balance | $ 30,000,000 |  |
Hercules and Silicon Valley Bank [Member] | Tranche One [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity under term loan |  | $ 20,000,000 |
Expiration date to borrow under a tranche for a debt instrument |  | Sep. 15, 2023 |
Hercules and Silicon Valley Bank [Member] | Tranche Two [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity under term loan |  | $ 10,000,000 |
Start date to borrow under a tranche for a debt instrument |  | Jan. 01, 2023 |
Expiration date to borrow under a tranche for a debt instrument |  | Dec. 15, 2023 |
Hercules and Silicon Valley Bank [Member] | Tranche Three [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity under term loan |  | $ 20,000,000 |
Start date to borrow under a tranche for a debt instrument |  | Sep. 15, 2023 |
Expiration date to borrow under a tranche for a debt instrument |  | Sep. 15, 2024 |
Hercules and Silicon Valley Bank [Member] | Tranche Four [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity under term loan |  | $ 25,000,000 |
Expiration date to borrow under a tranche for a debt instrument |  | Dec. 31, 2024 |
Hercules and Silicon Valley Bank [Member] | Option One Minimum Cash Debt Covenant [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Minimum cash balance as a percentage of loan amount outstanding |  | 40.00% |
Hercules and Silicon Valley Bank [Member] | Option Two Minimum Cash Debt Covenant [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Minimum cash balance as a percentage of loan amount outstanding |  | 25.00% |
Minimum market capitalization requirement for option |  | $ 750,000,000 |
Hercules and Silicon Valley Bank [Member] | Option Three Minimum Cash Debt Covenant [Member] | Second Amendment [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Minimum cash balance requirement to be met as a percentage of six-month product revenue against forecast |  | 70.00% |
Minimum percentage of net product revenues maintenance period |  | 6 months |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
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