Quarterly report pursuant to Section 13 or 15(d)

Net income (loss) per share (Details)

v3.8.0.1
Net income (loss) per share (Details) - shares
3 Months Ended 9 Months Ended
Apr. 30, 2018
Apr. 30, 2017
Apr. 30, 2018
Apr. 30, 2017
Unvested Restricted Stock [Member] | In the Money Stock Options [Member]        
Net income (loss) per share (Details) [Line Items]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 431,000   694,000  
Weighted Average Stock Options [Member]        
Net income (loss) per share (Details) [Line Items]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount   987,000   865,000
Outstanding Options [Member] | Out of the Money Stock Options [Member]        
Net income (loss) per share (Details) [Line Items]        
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 581,000 0 194,000 165,000