Acquisition-Related Restructuring Plan - Details of Future Cash Payments (Details) - USD ($) |
Apr. 30, 2017 |
Jul. 31, 2016 |
Aug. 01, 2008 |
Jul. 31, 2008 |
|---|---|---|---|---|
| Restructuring and Related Activities [Abstract] | ||||
| Future lease payments to be made | $ 2,300,000 | $ 3,327,000 | $ 2,100,000 | $ 2,100,000 |
| Interest expense to be accreted in future periods | 250,000 | |||
| Total remaining payments | $ 2,550,000 |