Collaboration Agreement - Schedule of Collaboration Revenue Related to U.S. XTANDI Net Sales (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]
Collaboration revenue related to U.S. XTANDI net sales	$ 165,129	$ 149,220	$ 318,922	$ 261,230
U.S. [Member] \| XTANDI [Member] \| Collaborative agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue related to U.S. XTANDI net sales	165,129	149,220	318,922	261,230
U.S. [Member] \| XTANDI [Member] \| Collaborative agreement [Member] \| Astellas Pharma Inc. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
U.S. XTANDI net sales (as reported by Astellas)	330,257	298,440	637,843	522,460
Shared U.S. development and commercialization costs	(95,055)	(84,947)	(225,639)	(195,260)
Pre-tax U.S. profit	235,202	213,493	412,204	327,200
U.S. [Member] \| XTANDI [Member] \| Collaborative agreement [Member] \| Medivation [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Medivation's share of pre-tax U.S. profit	117,601	106,747	206,102	163,600
Reimbursement of Medivation's share of shared U.S. costs	$ 47,528	$ 42,473	$ 112,820	$ 97,630

Dollar amount of collaboration revenue from net sales.

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- Definition

Pre-tax U.S. profit or loss under collaboration agreement with Astellas.

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No definition available.

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- Definition

U.S. Net sales of XTANDI as reported by collaboration partner, Astellas

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No definition available.

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Medivation's share of pre-tax U.S. profit or loss under collaboration agreement with Astellas

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No definition available.

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- Definition

Shared development and commercialization costs.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 45
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=68075638&loc=d3e60722-111653

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