Description of Business - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended	3 Months Ended
	Sep. 30, 2014 Country	Dec. 31, 2014 Scenario, Forecast [Member] Development milestone payments [Member]
Organization And Description Of Business [Line Items]
Number of countries in which XTANDI is approved for the post-docetaxel indication	45
Milestone payments earned		$ 45.0