Revenue earned from the amortization of non refundable upfront cash payment received under collaboration agreements over the expected performance period and milestone payments earned.

No definition available.

Name:	mdvn_CollaborationRevenueRelatedToUpFrontAndMilestonePayments
Namespace Prefix:	mdvn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Collaboration Agreements - Schedule of Collaboration Revenue (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Related to U.S. XTANDI sales									$ 339,902	$ 196,208	$ 35,752
Related to ex-U.S. XTANDI sales									49,476	6,338
Related to upfront and milestone payments									321,109	70,396	145,944
Collaboration revenue	$ 274,730mdvn_CollaborationRevenue	$ 200,478mdvn_CollaborationRevenue	$ 148,090mdvn_CollaborationRevenue	$ 87,189mdvn_CollaborationRevenue	$ 96,612mdvn_CollaborationRevenue	$ 60,027mdvn_CollaborationRevenue	$ 70,149mdvn_CollaborationRevenue	$ 46,154mdvn_CollaborationRevenue	$ 710,487mdvn_CollaborationRevenue	$ 272,942mdvn_CollaborationRevenue	$ 181,696mdvn_CollaborationRevenue