License and Collaboration Agreements - Schedule of Assets and Liabilities under Collaborative Arrangements (Detail) - License and Collaboration Agreements [Member] - Baxalta [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Accounts receivable, billed	$ 1,250	$ 1,336
Accounts receivable, unbilled	914	626
Deferred revenues	$ 88,217	$ 97,365