Notes Payable - Additional Information (Detail) - USD ($)		9 Months Ended
May 23, 2019	Sep. 30, 2019
Debt Instrument [Line Items]
Interest only, payment term		36 months
CRG Servicing LLC Agreement
Debt Instrument [Line Items]
Back end facility fee	$ 5,600,000
Bio Pharma Credit Plc
Debt Instrument [Line Items]
Secured credit term loan	60,000,000.0
Additional facility funds that can be obtained	20,000,000.0
Initial proceeds of term loan	60,000,000.0
Additional proceeds from debt	$ 1,800,000
Bio Pharma Credit Plc \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, term		72 months
Basis spread on variable rate		7.50%
Line of Credit \| CRG Servicing LLC Agreement \| Interest Expense
Debt Instrument [Line Items]
Deferred loan costs		$ 5,200,000
Debt instrument, unamortized discount		3,900,000
Loan prepayment fees and realized losses		$ 2,800,000

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- Definition

Additional borrowings made and the face value there of being represented

+ References

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- Definition

Additional Amount Of Debt Facility that Can be availed

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- Definition

Debt Instrument, Interest Only Payment Term

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- Definition

Loan Foreclosure Fees and The losses incurred

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- Definition

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

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

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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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Amount, after accumulated amortization, of debt discount.

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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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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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