Derivative Financial Instruments - Significant Assumptions Utilized in Binomial Lattice Process (Detail) - $ / shares	9 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Derivative [Line Items]
Quoted market price on valuation date	$ 2.5
Level 3 [Member] \| Minimum [Member]
Derivative [Line Items]
Range of market volatilities	83.60%	57.00%	59.90%
Risk free rates using zero coupon US Treasury Security rates	0.04%	0.02%	0.04%
Level 3 [Member] \| Maximum [Member]
Derivative [Line Items]
Range of market volatilities	106.30%	79.70%	73.90%
Risk free rates using zero coupon US Treasury Security rates	0.33%	0.58%	0.67%
Level 3 [Member] \| Derivative Financial Instruments, Assets [Member]
Derivative [Line Items]
Linked common shares	1,562,500	1,562,500	1,562,500
Quoted market price on valuation date	$ 0.36	$ 0.91	$ 0.93
Contractual exercise rate	$ 3.60	$ 3.60	$ 3.60
Term (years)	1 year 7 months 10 days	2 years 7 months 10 days	2 years 4 months 24 days

Fair Value Assumptions Linked Common Shares

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- Definition

Fair value assumptions quoted price.

+ References

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- Definition

Risk free rates using zero coupon country treasury security range of rates.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Agreed upon price for the exchange of the underlying asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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