Income taxes (Details) - (Provision) Benefit for income taxes were at rates different from U.S. federal statutory rates |
12 Months Ended | ||
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Jul. 31, 2017 |
Jul. 31, 2016 |
Jul. 31, 2015 |
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| (Provision) Benefit for income taxes were at rates different from U.S. federal statutory rates [Abstract] | |||
| Federal statutory rate | 34.00% | (34.00%) | 34.00% |
| Penalties and other expenses not deductible for income tax return purposes | (14.50%) | (1.10%) | (18.60%) |
| State income taxes, net of benefit of federal tax deduction | (2.10%) | (0.40%) | (0.50%) |
| Change in valuation allowance | 64.00% | 32.90% | (15.20%) |
| State tax law change | (82.80%) | ||
| Other | (2.00%) | 0.60% | |
| (3.40%) | (2.60%) | 0.30% | |
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- Definition Effective income tax rate reconciliation change in state and local income tax law. No definition available.
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- References No definition available.
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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 nondeductible expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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 other adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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