Capital units number of units sold to investors

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- Definition

Capital units price per unit

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- Definition

Class Of Warrant Or Right Exercise Period Of Warrants Or Rights

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- Definition

Class of warrant or right number of warrants or rights expired

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- Definition

Institutional Investors Units Warrants Issued Per Unit

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- Definition

Number of warrant exercised.

+ References

No definition available.

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- Definition

Proceeds From Issuance Of Common Stock And Warrants

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- Definition

Public Offered Units Series Warrants Issued Per Unit

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- Definition

Expiration date of warrants

+ References

No definition available.

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- Definition

Warrant Issued For Warrant Exercised

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No definition available.

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- Definition

Cost to investors of each class of capital shares or other capital units.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(b)(1))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

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- Definition

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

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 2

-Article 4

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- Definition

Cash received on stock transaction after deduction of issuance costs.

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No definition available.

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- Definition

Number of new stock issued during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Warrant Liability - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended	12 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 30, 2009	Dec. 31, 2011	Mar. 31, 2015
Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants						1.40
Proceeds from sale of stock	$ 1,652,000	$ 538,000	$ 3,078,000
November 2009 Financing [Member]
Class of Warrant or Right [Line Items]
Number of units sold to investors				1,000,000
Price per unit				$ 12.50
Gross proceeds from units sold to investors				12,500,000
Exercise price of warrants						15.00
Proceeds from sale of stock				11,985,000
November 2009 Financing [Member] \| Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of securities callable by each warrant or right warrants				0.40
Exercise price of warrants				$ 15.00
Number of securities callable by warrants				400,000
Number of warrants in each unit sold to institutional investors				1
December 2011 Financing [Member]
Class of Warrant or Right [Line Items]
Price per unit					$ 1.25
Proceeds from issuance of common stock and warrants					$ 10,000,000
Number of Series A warrants in each unit issued in public offering					1
December 2011 Financing [Member] \| Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Number of securities callable by warrants					8,000,000
Number of warrants exercised	1,180,015	384,534	2,198,571
Number of shares issued upon warrants exercise			2,700,000
December 2011 Financing [Member] \| Series B Warrant [Member]
Class of Warrant or Right [Line Items]
Number of securities callable by warrants					8,000,000
Term of warrant					90 days
Warrant expiration						2012-May-02
Number of warrants exercised			2,700,000
Number of warrants expired						5,300,000
December 2011 Financing [Member] \| Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of shares issued upon warrants exercise			2,700,000
Number of shares issued upon warrants exercise	1,180,015	384,534	2,198,571
December 2011 Financing [Member] \| Common Stock [Member] \| Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants					$ 1.40
December 2011 Financing [Member] \| Capital Units [Member] \| Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Number of securities callable by each warrant or right warrants					1
December 2011 Financing [Member] \| Capital Units [Member] \| Series B Warrant [Member]
Class of Warrant or Right [Line Items]
Number of securities callable by each warrant or right warrants					1
Warrant expiration						December 2016