Subsequent Event - Additional Information (Detail) - Credit Agreement - Term Loan - Andexxa		12 Months Ended
Feb. 28, 2019 USD ($) Tranche	Dec. 31, 2018
Subsequent Event [Line Items]
Debt instrument, interest rate terms		The outstanding principal balance of the term loan bears interest at a rate per annum equal to 9.75%, while upon the occurrence of an event of default, all outstanding obligations under the Credit Agreement will bear interest at a rate per annum equal to the sum of 9.75% plus 3.00%. All interest will be made on the basis of a 360-day year and actual days elapsed with interest accruing on the day the term loan is made.
Debt instrument, covenant description		The term loan is secured by substantially all of our assets. The Credit Agreement contains customary representations and warranties, and we are also subject to certain customary covenants that require us to deliver financial reports at designated times of the year and limit or restrict our ability to incur additional indebtedness or liens, acquire, own or make any investments, pay cash dividends or enter into certain corporate transactions, including mergers and changes of control, and require us to maintain a specified level of cash.
Debt instrument, debt default, event of default description		The Credit Agreement also contains customary events of default. In the case of a continuing event of default, the administrative agent would be entitled to exercise various remedies, including, without limitation, declaring the unpaid principal amount of the outstanding term loan, all interest accrued and unpaid thereon and all other amounts owing or payable under the Credit Agreement and related loan documents to be immediately due and payable.
Subsequent Event
Subsequent Event [Line Items]
Number of tranche \| Tranche	2
Debt instrument, maturity date	Feb. 28, 2025
Debt instrument, interest rate	9.75%
Percentage of interest rate on event of default	9.75%
Percentage of additional interest rate on event of default	3.00%
Subsequent Event \| Maximum
Subsequent Event [Line Items]
Aggregate principal amount	$ 125,000,000
Subsequent Event \| Closing Date of Agreement
Subsequent Event [Line Items]
Aggregate principal amount	62,500,000
Subsequent Event \| After Closing Date Until November 15, 2019
Subsequent Event [Line Items]
Aggregate principal amount	62,500,000
Minimum net sales required for issuance of debt	$ 50,000,000

Debt default interest rate.

No definition available.

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- Definition

Debt instrument additional interest rate on event of default.

+ References

No definition available.

+ Details

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- Definition

Minimum net sales required for issuance of debt.

+ References

No definition available.

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- Definition

Number of tranche.

+ References

No definition available.

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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-SubTopic 30
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- Definition

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

+ References

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- Definition

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.

+ References

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Discussion of the facts and amounts pertaining to each failure to comply with an affirmative or negative covenant of a long-term debt instrument, including violating payment terms or an inability to meet certain minimum financial requirements or achieve or maintain certain financial ratios. The discussion would generally be expected to also include whether or not the failure can and will be overcome and a description of the terms of any waivers, including the amount of the waiver and the period of time covered by the waiver, and if reclassification of long-term debt to current has been made in the current balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(c))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Name Accounting Standards Codification
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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