Income taxes (Details) - USD ($) $ in Thousands |
3 Months Ended | 5 Months Ended | 7 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|---|---|
Apr. 30, 2018 |
Apr. 30, 2017 |
Dec. 31, 2017 |
Jul. 31, 2018 |
Apr. 30, 2018 |
Apr. 30, 2017 |
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| Income taxes (Details) [Line Items] | ||||||
| Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 35.00% | |||||
| Effective Income Tax Rate Reconciliation, Percent | 0.00% | 24.10% | ||||
| Income Tax Expense (Benefit) (in Dollars) | $ 0 | $ (1,097) | $ 0 | |||
| Scenario, Plan [Member] | ||||||
| Income taxes (Details) [Line Items] | ||||||
| Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | |||||
| Alternate Minimum Tax [Member] | ||||||
| Income taxes (Details) [Line Items] | ||||||
| Effective Income Tax Rate Reconciliation, Tax Credit, Amount (in Dollars) | $ 1,100 | |||||
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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