Subsequent Events - Additional Information (Detail) (Subsequent Event [Member], USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended
Feb. 28, 2014 Employees
Subsequent Event [Line Items]
Tax incentive awarded	$ 0.6
State research and development tax credits monetized	0.6
Number of incremental employees pledged to be hired	31
Hercules [Member]
Subsequent Event [Line Items]
warrants to purchase	302,143
common stock for proceeds	$ 1.1

Represents the number of employees to be hired under the incentive program over a specified period of time.

No definition available.

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- Definition

Represents the state research and development tax credits monetized under the tax incentive and credit programs.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of tax incentives awarded under the tax incentive and credit programs.

+ References

No definition available.

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 2

-Article 4

+ Details

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

No definition available.

+ Details

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- Details

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