Term Loan Agreement (CRG) - Additional Information (Detail)	Feb. 21, 2017 USD ($) Warrant $ / shares shares
Debt Instrument [Line Items]
Remainder of borrowings	$ 13,700,000
CRG [Member]
Debt Instrument [Line Items]
Borrowings outstanding	45,000,000
Additional borrowing capacity upon milestone achievement	30,000,000
Second draw borrowing capacity upon milestone achievement	$ 5,000,000
Loan agreement term	6 years
Loan agreement interest only term	3 years
Loan agreement interest only term threshold	4 years
Agreement maturity date	Dec. 31, 2022
Interest on borrowings	12.50%
Interest on borrowings, interest only period percentage	3.50%
Effective interest on borrowings	9.00%
Final payment fee rate	9.00%
Prepayment period of outstanding principal and accrued unpaid interest	5 years
Prepayment fee after	$ 0
Additional interest rate	4.00%
Number of warrants \| Warrant	5
Warrants issued to purchase shares of common stock \| shares	1,701,583
Warrants exercisable period \| $ / shares	$ 2.38
CRG [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Additional borrowing capacity upon milestone achievement	$ 15,000,000
CRG [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Additional borrowing capacity upon milestone achievement	$ 15,000,000

Debt instrument interest only payment term.

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- Definition

Debt instrument interest only payment term threshold.

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- Definition

Debt instrument interest rate stated interest only period percentage.

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No definition available.

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- Definition

Debt instrument prepayment fee after year five.

+ References

No definition available.

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- Definition

Final payment fees percentage.

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No definition available.

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- Definition

Line of credit facility additional borrowing capacity upon contingent milestone achievement.

+ References

No definition available.

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- Definition

Line of credit facility second draw borrowing capacity upon contingent milestone achievement.

+ References

No definition available.

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- Definition

Number of warrants.

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- Definition

Prepayment period of outstanding principal and accrued unpaid interest.

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No definition available.

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- Definition

Remaining line of credit after deducting loan origination cost broker and other fees.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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