Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Apr. 30, 2015	Jul. 31, 2014
Net of allowance for doubtful accounts	$ 0	$ 0
Preferred stock, Par value	$ 0.01	$ 0.01
Preferred stock, Shares authorized	3,000	3,000
Preferred stock, Shares issued
Preferred stock, Shares outstanding
Treasury stock, shares	42
Common Stock [Member] | Class A common stock
Common stock, Par value	$ 0.01	$ 0.01
Common stock, Shares authorized	2,000	2,000
Common stock, Shares issued	787	787
Common stock, Shares outstanding	787	787
Common Stock [Member] | Class B common stock
Common stock, Par value	$ 0.01	$ 0.01
Common stock, Shares authorized	40,000	40,000
Common stock, Shares issued	11,226	11,013
Common stock, Shares outstanding	11,184	11,013