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Warrants exercisable, weighted average remaining contractual term.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ 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)(4))

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Stockholders' Equity - Summary of Warrants Outstanding to Purchase Common Stock (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 4.20	$ 5.00
Number Outstanding	3,196,100	4,192,927	4,279,919	4,553,251
Aggregate Intrinsic Value	$ 22,881	$ 9,146	$ 4,572
Minimum [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 3.12		$ 3.00
Maximum [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 5.00		$ 5.00
$0.00 - 5.00 [Member] \| Minimum [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 0.00
$0.00 - 5.00 [Member] \| Maximum [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 5.00
Midcap warrant [Member] \| $0.00 - 5.00 [Member]
Warrants, by Exercise Price Range [Line Items]
Number Outstanding	284
Weighted Average Remaining Contractual Life (Years)	3 months 22 days
Aggregate Intrinsic Value	$ 3
Midcap warrant [Member] \| $0.00 - 5.00 [Member] \| Weighted Average [Member]
Warrants, by Exercise Price Range [Line Items]
Range of Exercise Prices	$ 3.12