Provision for Income Taxes and Effective Tax Rate (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Apr. 30, 2017 |
Apr. 30, 2016 |
Apr. 30, 2017 |
Apr. 30, 2016 |
|
| Income Tax Disclosure [Abstract] | ||||
| (Benefit)/provision for income taxes | $ (4,882) | $ 1,722 | $ (1,934) | $ 2,863 |
| Effective tax rate | 8.00% | 26.00% | 4.00% | 46.00% |