Collaboration Agreement - Schedule of Collaboration Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Related to XTANDI net sales	$ 165,129	$ 149,220	$ 318,922	$ 261,230
Related to upfront and milestone payments		846		2,257
Collaboration revenue	206,165	175,657	388,662	304,845
Collaborative agreement [Member] | XTANDI [Member] | U.S. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Related to XTANDI net sales	165,129	149,220	318,922	261,230
Collaborative agreement [Member] | XTANDI [Member] | ex-U.S. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Related to XTANDI net sales	$ 41,036	$ 25,591	$ 69,740	$ 41,358