Provision for Income Taxes - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jan. 31, 2019 USD ($)	Jan. 31, 2019 USD ($)
Income Tax Disclosure [Abstract]
Effective income tax rate	389.10%	74.40%
Corporate income tax rate		21.00%
Expected decrease in unrecognized tax benefits due to resolution of uncertain tax positions	$ 4,000	$ 4,000
Expected decrease in interest due to resolution of uncertain tax positions		$ 900

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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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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The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

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