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- Definition

Class Of Warrant Expiration Date

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- Definition

Class of Warrant or Right, Exercised in Period

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- Definition

Class of Warrant or Right, Expired 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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- Definition

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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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 $)	3 Months Ended	0 Months Ended	12 Months Ended	0 Months Ended
	Mar. 31, 2015	Feb. 27, 2015	Dec. 31, 2014	Oct. 16, 2009
Derivative [Line Items]
Common stock issued under private placement, value	$ 52,253,000
Common stock issued under private placement, net proceeds	52,800,000
Warrants expiration date	Feb. 27, 2015
Warrants exercised	1,844,585
Proceed from exercise of warrants	2,713,000us-gaap_ProceedsFromWarrantExercises
Maximum
Derivative [Line Items]
Warrants outstanding			8,087,388
Prior To Agreement
Derivative [Line Items]
Warrants expiration date	Oct. 16, 2014
Warrants Issued October 2009
Derivative [Line Items]
Warrants outstanding	0
Warrants expiration date	Feb. 27, 2015
Warrants exercised	1,844,585
Proceed from exercise of warrants	2,700,000
Warrants expired		6,242,803
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		0
Warrants exercised			1,684,888
Proceed from exercise of warrants			1,700,000
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]
Warrant term				5 years
Warrants issued, number of shares called by a warrant				0.5
Exercise price of the warrants				$ 1.50
October 2009 Private Placement \| Warrants Issued October 2009 \| Bridge Loan \| American Depositary Share
Derivative [Line Items]
Warrant term				5 years
Warrants issued, number of shares called by a warrant				0.5
Exercise price of the warrants				$ 1.50