Number of shares of equity interests issued or issuable to acquire entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

Value of additional common stock for which the entity has committed to purchasing from collaborator, original

+ References

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- Definition

Value of consideration received by the entity for collaboration

+ References

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- Definition

Amount of potential future milestone payments under agreement, maximum

+ References

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- Definition

Percent of collaboration payments received pursuant to a collaboration agreement for upfront fees, milestones and royalties which will be paid to another party.

+ References

No definition available.

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- Definition

Number of shares of common stock of a third party to be distributed in the form of a common stock dividend.

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No definition available.

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Subsequent Events - Additional Information (Details) (USD $)	1 Months Ended
	May 31, 2015	Apr. 30, 2015	Mar. 31, 2015
ZIOPHARM Oncology, Inc.
Subsequent Event [Line Items]
Common stock purchase commitment			$ 50,000,000
ZIOPHARM Oncology, Inc. \| Subsequent Event
Subsequent Event [Line Items]
Shares of common stock	17,830,305
Common stock purchase commitment	43,500,000
Ares Trading S.A., a subsidiary of Merck Serono S.A. \| Subsequent Event
Subsequent Event [Line Items]
Consideration to be received upon achievement of future milestones	826,000,000
Ares Trading S.A., a subsidiary of Merck Serono S.A. \| ZIOPHARM Oncology, Inc. \| Subsequent Event
Subsequent Event [Line Items]
Percent of certain collaboration payments	50.00%
Upfront \| Ares Trading S.A., a subsidiary of Merck Serono S.A. \| Upfront and Milestone Payments \| Subsequent Event
Subsequent Event [Line Items]
Collaborative arrangement consideration received, value	115,000,000
Okanagan Specialty Fruits Inc. \| Subsequent Event
Subsequent Event [Line Items]
Percentage of outstanding common stock acquired		100.00%
Cash paid for acquisition		$ 10,000,000
Business acquisition, consideration paid, shares issued		707,853