Warranty (Details) - USD ($) $ in Millions |
6 Months Ended | |
|---|---|---|
Jan. 31, 2016 |
Jan. 31, 2015 |
|
| Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward] | ||
| Beginning balance | $ 8.6 | $ 9.0 |
| Accruals for warranties issued during the reporting period | 2.6 | 1.6 |
| Accruals related to pre-existing warranties (including changes in estimates) | 2.7 | (0.2) |
| Less settlements made during the period | (1.7) | (2.0) |
| Ending balance | $ 12.2 | $ 8.4 |