Summary of Significant Accounting Policies - Basic and Diluted Net Loss per Share Computations (Detail) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Accounting Policies [Abstract]
Net loss from continuing operations	$ (9,350,701)	$ (7,562,528)
Net loss from discontinued operations		(57,728)
Net loss	$ (9,350,701)us-gaap_NetIncomeLoss	$ (7,620,256)us-gaap_NetIncomeLoss
Weighted average shares outstanding used to compute basic and diluted net income or loss per share	69,219,964	55,343,877
Basic and diluted net loss per share from continuing operations	$ (0.14)	$ (0.14)
Basic and diluted net loss per share from discontinued operations	$ 0	$ 0
Basic and diluted net loss per share	$ (0.14)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.14)us-gaap_EarningsPerShareBasicAndDiluted

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

No definition available.

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- Definition

Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

+ References

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

+ References

No definition available.

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- Definition

Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683

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- Definition

Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

+ References

No definition available.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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-SubTopic 10

-Section 50

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-Glossary Other Comprehensive Income

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-Name Accounting Standards Codification

-Glossary Net Income

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.19)

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-Section S99

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-Subparagraph (SX 210.5-03.18)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 5

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- Definition

Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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No definition available.

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