Notes Payable - Additional Information (Detail) - USD ($)		12 Months Ended
May 23, 2019	Dec. 31, 2020
Bio Pharma Credit Plc
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 60,000,000
Additional facility that can be obtained	20,000,000
Debt instrument, face amount	60,000,000
Additional borrowing of face amount	1,800,000
Loan agreement term		72 months
Loan agreement interest only term		36 months
Bio Pharma Credit Plc \| LIBOR
Debt Instrument [Line Items]
Additional interest rate		7.50%
Bio Pharma Credit Plc \| LIBOR \| Minimum
Debt Instrument [Line Items]
Additional interest rate		2.00%
CRG
Debt Instrument [Line Items]
Back end facility fee	$ 5,600,000
CRG \| Interest Expense
Debt Instrument [Line Items]
Debt issuance costs		$ 5,200,000
Amortization of discount		3,900,000
Loan preclosure fees		$ 2,800,000

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- Definition

Debt Instrument Additional Borrowings Face Amount

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- Definition

Debt Instrument Additional Facility That Can Be Obtained

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- Definition

Debt instrument interest only payment term.

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No definition available.

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- Definition

Loan Preclosure Fees And Realized Losses

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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