- Definition

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.

+ References+ Details

Asset Acquisition and License Agreements - Additional Information (Detail) (USD $)	6 Months Ended		12 Months Ended			1 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended			12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Nov. 30, 2007 Millennium	Dec. 31, 2009 Millennium	Dec. 31, 2009 Millennium Series C Convertible Preferred Stock	Nov. 30, 2007 Millennium Maximum	Dec. 31, 2011 Astellas Pharma Inc	Dec. 31, 2008 Astellas Pharma Inc	Dec. 31, 2012 Astellas Pharma Inc	Dec. 31, 2012 Astellas Pharma Inc Maximum
Asset Acquisition [Line Items]
License fees paid						$ 5,000,000	$ 250,000			$ 7,200,000	$ 1,000,000
Research and Development Expense	38,556,000	26,049,000	49,717,000	46,089,000	43,260,000	5,000,000		250,000		7,200,000
Additional license fees payable on occurrence of specified events									$ 35,000,000				$ 71,500,000
Convertible preferred stock, shares issued as payment								17,667
Share price								$ 14.15
Percentage required to pay for any payment received under collaboration excluding royalties												20.00%