License agreement milestone payment.

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- Definition

United States Bankruptcy Court where petition for bankruptcy was filed.

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Description of the bankruptcy proceedings, including the process for emergence from bankruptcy. Does not include a description of management's plans to improve operations to enable the entity to emerge from bankruptcy, or a description of planned facility closings, business exit activities and headcount reduction plans.

+ References

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

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Licensing Agreements - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development	$ 4,701,000us-gaap_ResearchAndDevelopmentExpense	$ 2,928,000us-gaap_ResearchAndDevelopmentExpense	$ 2,648,000us-gaap_ResearchAndDevelopmentExpense	$ 1,495,000us-gaap_ResearchAndDevelopmentExpense	$ 1,440,000us-gaap_ResearchAndDevelopmentExpense	$ 1,586,000us-gaap_ResearchAndDevelopmentExpense	$ 3,195,000us-gaap_ResearchAndDevelopmentExpense	$ 3,479,000us-gaap_ResearchAndDevelopmentExpense	$ 11,772,000us-gaap_ResearchAndDevelopmentExpense	$ 9,700,000us-gaap_ResearchAndDevelopmentExpense	$ 15,807,000us-gaap_ResearchAndDevelopmentExpense
Calando Pharmaceuticals, Inc. [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Bankruptcy proceedings, court where petition was filed									District of Delaware
Bankruptcy petition date filed									Mar. 03, 2015
Bankruptcy description									In March 2014, Calando entered Chapter 7 bankruptcy in the District of Delaware and, as a result, the intellectual property rights the Company has obtained from Calando are subject to potential risks that may arise in connection with bankruptcy.
MIT License Agreement [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development									10,000	10,000	10,000
Calando Product License Agreement [Member] \| Upon achievement of specified regulatory and commercial milestones [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment									32,800,000
Calando Platform License Agreement [Member] \| CRLX301 [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development									250,000
Calando Platform License Agreement [Member] \| Upon achievement of specified regulatory and commercial milestones [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment									17,800,000
Calando Platform License Agreement [Member] \| Upon initiation of phase one clinical trial [Member] \| CRLX301 [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment									250,000
SUNY License Agreement [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development									$ 30,000	$ 25,000	$ 10,000