Derivative Financial Instruments - Significant Assumptions Utilized in Binomial Lattice Process (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Derivative [Line Items]
Quoted market price on valuation date	2.50omex_FairValueAssumptionsQuotedPrice
Warrant Group 1 [Member] \| Level 3 [Member] \| Minimum [Member]
Derivative [Line Items]
Range of market volatilities		50.10%
Risk free rates using zero coupon US Treasury Security rates		0.01%
Warrant Group 1 [Member] \| Level 3 [Member] \| Maximum [Member]
Derivative [Line Items]
Range of market volatilities		88.30%
Risk free rates using zero coupon US Treasury Security rates		0.07%
Warrant Group 1 [Member] \| Level 3 [Member] \| Derivative Financial Instruments, Assets [Member]
Derivative [Line Items]
Linked common shares		525,000
Quoted market price on valuation date		2.02
Contractual exercise rate		2.3793
Term (years)		3 months 11 days
Warrant Group 2 [Member] \| Level 3 [Member] \| Minimum [Member]
Derivative [Line Items]
Range of market volatilities	59.90%	51.10%
Risk free rates using zero coupon US Treasury Security rates	0.04%	0.07%
Warrant Group 2 [Member] \| Level 3 [Member] \| Maximum [Member]
Derivative [Line Items]
Range of market volatilities	73.90%	78.20%
Risk free rates using zero coupon US Treasury Security rates	0.67%	0.78%
Warrant Group 2 [Member] \| Level 3 [Member] \| Derivative Financial Instruments, Assets [Member]
Derivative [Line Items]
Linked common shares	1,562,500	1,562,500
Quoted market price on valuation date	0.93	2.02
Contractual exercise rate	3.60	3.60
Term (years)	2 years 4 months 24 days	3 years 4 months 6 days
Custom lattice variable: Probability of exercisability (434,027 linked common shares)	0.00%	0.00%

Fair Value Assumptions Linked Common Shares

No definition available.

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- Definition

Fair value assumptions quoted price.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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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

No definition available.

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

+ 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 (bbb)

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

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