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Equity Financings and Warrants (Details Textual) - USD ($) $ / shares in Units, $ in Millions				6 Months Ended
	Jun. 16, 2015	Feb. 07, 2014	Feb. 03, 2014	Jun. 30, 2015	Dec. 31, 2014
Equity Financings And Warrants (Textual) [Abstract]
Common stock, shares issued				63,219,990	21,150,486
PIPE Transaction
Equity Financings And Warrants (Textual) [Abstract]
Common stock, shares issued	42,021,579
Warrants available to purchase additional commons shares	16,808,632
Purchase price for common stock unit	$ 0.8805
Proceeds from issuance of common stock, net of financing costs	$ 34.0
Warrant coverage ratio	0.4
Warrants will become exercisable date				Dec. 13, 2015
Warrants were exercisable upon issuance, expiry year	7 years
Warrant price per share	$ 0.8716
PIPE Transaction | Security Units
Equity Financings And Warrants (Textual) [Abstract]
Common stock, shares issued	42,021,579
Registered Direct Offering
Equity Financings And Warrants (Textual) [Abstract]
Common stock, shares issued		5,116,228
Warrants available to purchase additional commons shares		1,279,057
Purchase price for common stock unit		$ 1.70
Proceeds from issuance of common stock, net of financing costs		$ 7.9
Warrant coverage ratio		0.25
Warrants were exercisable upon issuance, expiry year			5 years
Warrant price per share			$ 2.125
Closing bid price of the common stock			125.00%

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Equity financings and warrants.

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Date the warrants or rights are exercisable, in CCYY-MM-DD format.

+ 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)(3))



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

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 235



-SubTopic 10



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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 210



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