Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares |
Apr. 30, 2017 |
Jul. 31, 2016 |
|---|---|---|
| Stockholders’ equity: | ||
| Preferred stock, par value (in dollars per share) | $ 0.10 | $ 0.10 |
| Preferred stock, shares authorized (in shares) | 2,000,000 | 2,000,000 |
| Preferred stock, shares issued (in shares) | 0 | 0 |
| Common stock, par value (in dollars per share) | $ 0.10 | $ 0.10 |
| Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
| Common stock, shares issued (in shares) | 38,603,033 | 38,367,997 |
| Treasury stock, shares (in shares) | 15,033,317 | 15,033,317 |