Collaboration Agreements - Schedule of Collaboration Revenue (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Collaborative Arrangements [Line Items]
Attributable to ex-U.S. XTANDI sales	$ 500		$ 500
Total	70,149	42,912	116,303	79,737
U.S. XTANDI sales [Member]
Collaborative Arrangements [Line Items]
Attributable to U.S. XTANDI sales	41,201		78,890
Attributable to ex-U.S. XTANDI sales	482		482
Up-front cash payment arrangement [Member]
Collaborative Arrangements [Line Items]
Attributable to up-front and milestone payments	$ 28,466	$ 42,912	$ 36,931	$ 79,737