Commitments and Contingencies - Additional Information (Detail)		12 Months Ended
	Dec. 31, 2010 USD ($) Program	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 15, 2005 USD ($)
Commitments And Contingencies [Line Items]
Operating leases rent expense		$ 1,300,000	$ 1,300,000
Other noncurrent liability		3,000,000	3,000,000
Royalties due to both related and unrelated parties on license revenue accrued		201,000	177,000
Milestones payments yet to be achieved		2,000,000	2,000,000
Milestones payment		$ 0	$ 0
Anawah, Inc [Member]
Commitments And Contingencies [Line Items]
Contingent liability	$ 3,000,000			$ 5,000,000
Date of merger and reorganization		Jun. 15, 2005
Restructuring activities, description		As of December 31, 2010, the Company ceased activities relating to three of the six Anawah product programs
Number of development programs ceased | Program	3
Number of development programs | Program	6
Other noncurrent liability		$ 3,000,000
Minimum [Member]
Commitments And Contingencies [Line Items]
Operating leases, term of contract		3 years
Royalty payments due, percentage of net revenue as defined in the In-Licensing agreements		2.00%
Maximum [Member]
Commitments And Contingencies [Line Items]
Operating leases, term of contract		5 years
Royalty payments due, percentage of net revenue as defined in the In-Licensing agreements		15.00%