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- Definition

Class Of Warrant Expiration Date

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Class of Warrant or Right, Exercised in Period

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- Definition

Class of Warrant or Right, Issued

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- Definition

Class of Warrant or Right, Term

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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.

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- Definition

Number of warrants or rights outstanding.

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- Definition

The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Identification of the host contract (such as a debt instrument, lease, an agreement to settle payments in other than the functional currency), description of the terms of the contract, and discussion of a hybrid instrument with an embedded feature which is separated from the host contract and accounted for as a derivative.

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- Definition

Amount per share or per unit assigned to the consideration received of equity securities issued for development stage entities.

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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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

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No definition available.

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Warrants and Warrant Derivative Liability - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended			0 Months Ended
	Oct. 31, 2009	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 16, 2009
Derivative [Line Items]
Warrants outstanding		8,087,388
Exercise Price		$ 1.50
Warrants expiration date	Feb. 27, 2015
Proceed from exercise of warrants		$ 1,651,000us-gaap_ProceedsFromWarrantExercises	$ 160,000us-gaap_ProceedsFromWarrantExercises	$ 16,720,000us-gaap_ProceedsFromWarrantExercises
Prior To Agreement
Derivative [Line Items]
Warrants expiration date	Oct. 16, 2014
Warrants Issued October 2009
Derivative [Line Items]
Exercise Price		$ 1.50
Warrants expiration date		Feb. 27, 2015
Warrants Issued October 2009 \| Maximum
Derivative [Line Items]
Warrants outstanding		8,087,388
Warrants Issued October 2009 \| Prior To Agreement
Derivative [Line Items]
Warrants expiration date		Oct. 16, 2014
Warrants Issued July 2009
Derivative [Line Items]
Warrants outstanding		0
Warrants exercised		1,684,888	120,000
Proceed from exercise of warrants		1,700,000	100,000
October 2009 Private Placement
Derivative [Line Items]
Common stock issued under private placement, value					70,000,000
Common stock issued under private placement, net proceeds					62,300,000
Common stock issued under private placement, shares					66,400,000
Number of shares that each ADS represents					1
Common stock issued under private placement, price per share					$ 1.00
October 2009 Private Placement \| Warrants issued to three former officers
Derivative [Line Items]
Number of warrants issued					900,000
October 2009 Private Placement \| Bridge Loan
Derivative [Line Items]
Bridge notes converted in conjunction with the private placement, amount					$ 3,600,000
Common stock issued under private placement, shares					4,000,000
Number of shares that each ADS represents					1
Bridge notes converted in conjunction with the private placement, price per share					$ 0.90
October 2009 Private Placement \| Warrants Issued October 2009
Derivative [Line Items]
Number of warrants issued					35,200,000
Description of pricing variability feature and classification of warrants		The warrants issued in connection with the October 2009 financing contained a pricing variability feature which provided for an increase to the exercise price if the exchange rate between the U.S. dollar and British pound adjusts such that the warrants could be exercised at a price less than the £0.5 par value of the common stock - that is, if the exchange rate exceeded U.S. $3.00 per £1.0 sterling. Due to the potential variable nature of the exercise price, the warrants are not considered to be indexed to the Company’s common stock. Accordingly, the warrants do not qualify for the exception to classify the warrants within equity and are classified as a derivative liability.
October 2009 Private Placement \| Warrants Issued October 2009 \| Maximum
Derivative [Line Items]
Warrants issued, number of shares called by the warrant		36,100,000
October 2009 Private Placement \| Warrants Issued October 2009 \| American Depositary Share
Derivative [Line Items]
Exercise Price					$ 1.50
Warrant term					5 years
Warrants issued, number of shares called by a warrant					0.5
October 2009 Private Placement \| Warrants Issued October 2009 \| Bridge Loan \| American Depositary Share
Derivative [Line Items]
Exercise Price					$ 1.50
Warrant term					5 years
Warrants issued, number of shares called by a warrant					0.5