Reconciliation of Federal Statutory Income Tax (Detail)	12 Months Ended
May 31, 2017	May 31, 2016
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	0.00%	0.00%
Derivative gain/loss	2.80%	0.90%
Loss on debt conversion		(0.80%)
Inducement expense	(1.00%)	(1.00%)
Miscellaneous	(0.10%)	(0.50%)
Valuation allowance	(35.70%)	(32.90%)
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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Schedule Of Income Taxes [Line Items]

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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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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