The amount of the grant awarded from a governmental agency.

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Represents the number of months that the entity believes it will complete the earnings process and will be able to recognize the deferred collaboration amount as revenue.

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Represents the period of the grant.

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- Definition

The forfeiture rate assumption that is used in valuing an option on its own shares.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 07-4

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Revenue earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Subparagraph (SX 210.5-03.1(e))

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Summary of Significant Accounting Policies (Details 2) (USD $)	1 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended
	Mar. 31, 2011	Sep. 30, 2011	Sep. 30, 2012 item	Sep. 30, 2011	Mar. 31, 2012
Grant Revenue
Amount of grant awarded for development of STA-9584 in advanced prostate cancer	$ 1,000,000
Period of grant					1 year
Grant revenues		$ 521,000	$ 147,000	$ 732,000	$ 1,000,000
Deferred Collaboration Revenue
Number of months Company will recognize deferred revenue as revenue			12
Stock-Based Compensation
Forfeiture rate (as a percent)			10.00%
Segment Reporting
Number of operating segments			1
Common stock options
Basic and Diluted Loss Per Common Share
Outstanding securities not included in the computation of diluted net loss per common share as their inclusion would be anti-dilutive			6,007,123	5,918,559
Unvested restricted common stock
Basic and Diluted Loss Per Common Share
Outstanding securities not included in the computation of diluted net loss per common share as their inclusion would be anti-dilutive			58,936	86,871