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Face (par) amount of debt instrument at time of issuance.

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Term Loan - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
Term Loan - Additional Information (Details) - USD ($)	Oct. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 20, 2019
Debt Instrument [Line Items]
Issuance of term loan		$ 10,000,000
SVB-WestRiver Loan Agreement
Debt Instrument [Line Items]
Term loan, principal amount					$ 6,000,000.0
Increase in fair value of warrant liability				$ 8,000
SVB-WestRiver Loan Agreement \| Compound Derivative Liability
Debt Instrument [Line Items]
Fair value of compound derivative liability		51,000
Increase in fair value of compound derivative liability				$ 658,000
SVB-WestRiver Loan Agreement \| Series B Convertible Preferred Stock
Debt Instrument [Line Items]
Warrant liability converted into common stock		400,000
Oxford-SVB Loan Agreement
Debt Instrument [Line Items]
Issuance of term loan	$ 9,300,000
Draw an additional loan	$ 50,000,000.0
Interest rate terms	Borrowings under the Loan Agreement bear interest at a floating rate per annum equal to the greater of (i) 1-month term Secured Overnight Financing Rate, or SOFR, and (ii) 2.33%, plus 6.25%. The minimum per annum interest rate is 8.58%.
Maturity date	Oct. 01, 2027
Incremental prepayment amount	$ 10,000,000.0
Percentage of fee amount paid upon final payment	6.00%
Debt default rate	5.00%
Interest expense		$ 200,000
deduction of debt issuance costs	$ 700,000
Oxford-SVB Loan Agreement \| Term Loan
Debt Instrument [Line Items]
Interest expense			$ 0
Outstanding debt			$ 0
Oxford-SVB Loan Agreement \| Fixed Rate
Debt Instrument [Line Items]
Basis spread rate	6.25%
Oxford-SVB Loan Agreement \| Base Rate
Debt Instrument [Line Items]
Basis spread rate	8.58%
Oxford-SVB Loan Agreement \| Tranche A
Debt Instrument [Line Items]
Issuance of term loan	$ 10,000,000.0
Draw an additional loan	40,000,000.0
Oxford-SVB Loan Agreement \| Tranche B
Debt Instrument [Line Items]
Available borrowing capacity upon achievement of milestones	12,500,000
Oxford-SVB Loan Agreement \| Tranche C
Debt Instrument [Line Items]
Available borrowing capacity upon achievement of milestones	12,500,000
Oxford-SVB Loan Agreement \| Tranche D
Debt Instrument [Line Items]
Available borrowing capacity at lender's discretion	25,000,000.0
Oxford-SVB Loan Agreement \| Maximum \| Secured Term Loan Facility
Debt Instrument [Line Items]
Term loan, principal amount	$ 100,000,000.0
Oxford-SVB Loan Agreement \| Minimum
Debt Instrument [Line Items]
Basis spread rate	2.33%
Oxford-SVB Loan Agreement \| Minimum \| Term Loan \| Intellectual Property
Debt Instrument [Line Items]
Outstanding balance of loan threshold at which Intellectual Property becomes collateral	$ 75,000,000.0