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Collaboration and License Agreements - Additional Information 5 (Detail) (USD $)			1 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Oct. 31, 2010 Pfizer [Member] Molecule	Jun. 30, 2013 Pfizer [Member]	Jun. 30, 2014 Pfizer [Member] Program	Jun. 30, 2013 Pfizer [Member]
License And Collaboration Agreements [Line Items]
Collaboration agreement date					October 2010
Period of agreement					3 years
Commercialization of molecules			2
Non-refundable upfront payment			$ 5,000,000
Clinical milestone payments	5,000,000				17,000,000
Sales milestone payments					195,000,000
DART program					1
Research obligation completion date					2014-01
Recognized revenue under agreement				1,000,000		2,200,000
Deferred revenue	$ 20,684,000	$ 20,267,000			$ 0

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Aggregate potential clinical milestone payments available to be earned under collaboration agreement.

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- Definition

Aggregate potential remaining sales milestone payments available to be earned under collaboration agreement.

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- Definition

Collaboration and license agreement entered date.

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- Definition

Collaborative agreement period of contract.

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- Definition

Initial fee received from collaboration or license agreement.

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- Definition

Number of molecules to be developed and commercialized as per collaborations.

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Number of programs.

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Research obligation completion date.

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- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

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-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765



Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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