Fortress Biotech, Inc. Quarterly report pursuant to Section 13 or 15(d)

Sponsored Research and Clinical Trial Agreements - Additional Information (Detail)

v3.8.0.1

Sponsored Research and Clinical Trial Agreements - Additional Information (Detail) - USD ($)		3 Months Ended
	Mar. 12, 2018	Mar. 31, 2018	Mar. 31, 2017
Research And Development Expense		$ 12,000
Columbia University [Member]
Research And Development Expense		11,000	$ 0
Research and Development Arrangement, Contract to Perform for Others, Costs Incurred, Gross	$ 100,000
University of Texas [Member]
Research And Development Expense		82,500
University of North Carolina [Member]
Research And Development Expense		200,000
Checkpoint Therapeutics, Inc [Member]
Research And Development Expense		31,000	$ 200,000
Mustang Therapeutics Inc [Member]
Research And Development Expense		100,000
Payments Made to Fund for Research Program		$ 900,000
Research Program Fund		2 years
Upfront Prepayment		$ 900,000
Proceeds For Research Program		600,000
Umass Sponsored Research Agreement [Member]
Research And Development Expense		100,000
Sponsor Research Agreement, Funding Commitment		800,000
Payments For Research And Development Expenses		800,000
UNC Sponsored Research Agreement [Member]
Sponsor Research Agreement, Funding Commitment		$ 2,300,000
UNC Sponsored Research Agreement [Member] \| UNC [Member]
Sponsor Research Agreement Term		3 years
UNC Sponsored Research Agreement [Member] \| Tamid [Member]
Payments For Research And Development Expenses		$ 800,000

- Definition

The amount of cash outflow associated research and development expenses paid during the period.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

The cash outflow to fund research program.

+ References

No definition available.

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Namespace Prefix:	fbio_
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- Definition

Cash in folw associated with research program.

+ References

No definition available.

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Namespace Prefix:	fbio_
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Balance Type:	debit
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- Definition

It represents the term of Research Program Fund.

+ References

No definition available.

+ Details

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Namespace Prefix:	fbio_
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- Definition

The amount of funding commitment for a sponsor research agreement.

+ References

No definition available.

+ Details

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- Definition

These lines are represents that sponser research agreement term.

+ References

No definition available.

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- Definition

The amount of upfront prepayment as at reporting period.

+ References

No definition available.

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Namespace Prefix:	fbio_
Data Type:	xbrli:monetaryItemType
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- Definition

The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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