Collaboration Agreement - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research term, in months	30 months
Upfront payment received	$ 1,750,000
Collaboration revenue	203,000
Revenues	229,000	$ 244,000
Milestone payments receivable	25,000,000.0
Milestone or royalty payments received	0
Upon the Achievement of Specified Preclinical and Clinical Development Milestone Events
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payments receivable	10,000,000.0
Upon the Achievement of Specified Regulatory Milestone Events
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payments receivable	$ 15,000,000.0

Collaboration Revenue

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- Definition

Estimated Milestone Payment To Be Received

+ References

No definition available.

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- Definition

Research Term

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Cash received from collaborators during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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- Definition

Cash received for royalties during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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