Commitments and Contingencies - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016 USD ($) ft²	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)
Commitments And Contingencies [Line Items]
Operating lease office space, in square feet | ft²	158,000
Lease expiry period	2019-12
Total consideration under current statement of work				$ 15,200,000
Partial payment consideration under current statement of work	$ 6,200,000
MDV9300 [Member]
Commitments And Contingencies [Line Items]
Manufacturing services and supply agreement period	3 years
Upfront and setup fees		$ 100,000	$ 200,000	$ 3,000,000
Potential payment upon completion of Manufacturing Technology Transfer	$ 5,000,000
Funding for clinical trial materials	$ 19,300,000
Funding period for clinical materials	3 years
Clinical trial materials amount paid	$ 9,000,000
Development milestone payments [Member]
Commitments And Contingencies [Line Items]
Aggregate milestone payments upon achievement of certain development and regulatory milestone events	$ 2,800,000
Percentage of sublicensing income	10.00%
Royalty percentage on sales	4.00%
Corporate Headquarters [Member]
Commitments And Contingencies [Line Items]
Operating lease office space, in square feet | ft²	143,000
Optional lease extension term	5 years