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Notes Payable - Narratives (Details) $ in Thousands			1 Months Ended	3 Months Ended	9 Months Ended
Notes Payable - Narratives (Details) $ in Thousands	May 11, 2021 USD ($) tranche	May 11, 2011 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Contractual exit fee			$ 900	$ 900	$ 900
Interest Expense				678	1,029
Amortization of debt issuance costs					319
Oaktree Capital Management LP Credit Agreement
Debt Instrument [Line Items]
Term of loan facility	5 years
Maximum borrowing capacity available under the credit agreement	$ 125,000
Number of tranches \| tranche	5
Additional borrowing capacity available, subject to certain milestone events	$ 80,000
Proceeds from line of credit	$ 15,000		30,000
Accrued interest rate (as a percent)	11.50%
Percentage of periodic principal payment	5.00%
Upfront fee (as a percent)	2.00%
Commitment fees	0.75%
Commitment fee accrual period	120 days
Percentage of term loan exit fees	2.00%
Debt issuance costs	$ 4,400		1,200	1,200	1,200
Contractual exit fee	300		$ 600	$ 600	600
Interest Expense					1,000
Interest on term loan					700
Amortization of debt issuance costs					$ 300
Oaktree Capital Management LP Credit Agreement \| Funding of the tranche A- 2 term loans until the funding of the tranche B term loans
Debt Instrument [Line Items]
Minimum liquidity to be maintained	20,000
Oaktree Capital Management LP Credit Agreement \| Funding date of the tranche B term loans until the maturity of the Term Loans
Debt Instrument [Line Items]
Minimum liquidity to be maintained	$ 15,000
Oaktree Capital Management LP Credit Agreement \| Scenario Of Prepayment On Or Before May 11, 2023
Debt Instrument [Line Items]
Prepayment premium (as a percent)	4.00%
Oaktree Capital Management LP Credit Agreement \| Scenario Of Prepayment Occurs Between May 11, 2023 To May 11, 2024
Debt Instrument [Line Items]
Prepayment premium (as a percent)	4.00%
Oaktree Capital Management LP Credit Agreement \| Scenario Of Prepayment Between May 11, 2024 To May 11, 2025
Debt Instrument [Line Items]
Prepayment premium (as a percent)	2.00%
Oaktree Capital Management LP Credit Agreement \| Scenario Of Prepayment After May 11, 2025
Debt Instrument [Line Items]
Prepayment premium (as a percent)	0.00%
Oaktree Capital Management LP Credit Agreement \| Prepayment occurs on or before May 11, 2022
Debt Instrument [Line Items]
Prepayment premium (as a percent)	12.50%
Oaktree Capital Management LP Credit Agreement \| Prepayment occurs after May 11, 2022 but on or before May 11, 2023
Debt Instrument [Line Items]
Prepayment premium (as a percent)	10.00%
Oaktree Capital Management LP Credit Agreement \| Term Loans Tranche A-1
Debt Instrument [Line Items]
Proceeds from line of credit		$ 15,000
Oaktree Capital Management LP Credit Agreement \| Term Loans Tranche A-2
Debt Instrument [Line Items]
Proceeds from line of credit	$ 30,000
Oaktree Capital Management LP Credit Agreement \| Term Loan Tranche B
Debt Instrument [Line Items]
Additional borrowing capacity available, subject to certain milestone events	30,000
Oaktree Capital Management LP Credit Agreement \| Term Loan Tranche C
Debt Instrument [Line Items]
Additional borrowing capacity available, subject to certain milestone events	25,000
Gross proceeds from sublicense, minimum	40,000
Net proceeds from sublicense, minimum	36,000
Oaktree Capital Management LP Credit Agreement \| Term Loan Tranche D
Debt Instrument [Line Items]
Additional borrowing capacity available, subject to certain milestone events	25,000
Net product revenue, minimum	$ 50,000
Net product revenue, consecutive earning period	6 months