CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jan. 31, 2018	Jul. 31, 2017
Statement Of Financial Position [Abstract]
Allowances for accounts receivables	$ 237	$ 263
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	15,503,290	11,889,649
Common stock, shares outstanding	15,503,290	11,889,649