Spin-off of Idun Pharmaceuticals, Inc. - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
Jan. 31, 2013	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Change in equity as a result of spin-off		$ (500,000)
Idun Pharmaceuticals, Inc. [Member]
Restructuring Cost and Reserve [Line Items]
Change in equity as a result of spin-off	$ 500,000
Idun Pharmaceuticals, Inc. [Member] \| Spin-off [Member]
Restructuring Cost and Reserve [Line Items]
Payments for restructuring	$ 500,000

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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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.

+ References

No definition available.

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- Definition

The change in equity as a result of a spin-off transaction (a regular or reverse spin-off) which is based on the recorded amounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Spinoff
-URI http://asc.fasb.org/extlink&oid=6749415

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 60
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6406278&loc=d3e26268-112671

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reverse Spinoff
-URI http://asc.fasb.org/extlink&oid=6524171

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