Reconciliation of Federal Statutory Income Tax Rate of 34 Percent to Effective Income Tax Rate (Detail)	12 Months Ended
May 31, 2016	May 31, 2015
Schedule Of Income Taxes [Line Items]
Income tax provision at statutory rate	34.00%	34.00%
State income taxes, net	0.00%	0.00%
Rate change		(0.60%)
Derivative gain/loss	0.90%	(1.20%)
Loss on debt conversion	(0.80%)
Inducement charge	(1.00%)
Miscellaneous	(0.50%)
Valuation allowance	(32.90%)	(32.20%)
Total	0.00%	0.00%

Effective Income Tax Rate Reconciliation, Derivative Gain Loss, Percent

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Effective Income Tax Rate Reconciliation Inducement Charge

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Effective Income Tax Rate Reconciliation Loss On Debt Conversion

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Effective Income Tax Rate Reconciliation Miscellaneous

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Schedule Of Income Taxes [Line Items]

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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