Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Apr. 11, 2019	Apr. 04, 2019
Subsequent Event [Line Items]
License arrangement upfront payment		$ 30.0
Percentage of net sales pertaining to additional royalties		1.00%
Stock issued during period, shares, new issues	12,000,000
Sale of stock, price per share	$ 5.00
Sale of stock, number of shares issued in transaction	10,000,000
Proceeds from issuance common stock before underwriters discounts and commissions and offering expenses	$ 50.0
Proceeds from issuance common stock net of underwriters discounts and commissions and offering expenses	47.5
Gross proceeds to selling stockholder from public offering	$ 10.0
Minimum [Member]
Subsequent Event [Line Items]
Percentage of royalty on sales		8.50%
Maximum [Member]
Subsequent Event [Line Items]
Percentage of royalty on sales		17.50%
First Installment [Member]
Subsequent Event [Line Items]
License arrangement upfront payment		$ 20.0
Second Installment [Member]
Subsequent Event [Line Items]
License arrangement upfront payment		$ 10.0

License arrangement upfront payment.

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- Definition

Percentage of net sales pertaining to additional royalties.

+ References

No definition available.

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- Definition

Percentage of royalty on sales.

+ References

No definition available.

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- Definition

Proceeds From Issuance Of Common Stock After Underwriting Discounts Commissions And Other Expenses

+ References

No definition available.

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- Definition

Proceeds From Issuance Of Common Stock Before Underwriting Discounts Commissions And Other Expenses

+ References

No definition available.

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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