Earnings (Loss) Per Share (Details 1) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017
Stock options excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted earnings per share	1,444	485	1,444	20
Non-vested restricted Class B common stock [Member]
Stock options excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted earnings per share	191	212	191
Stock options [Member]
Stock options excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted earnings per share	1,253	273	1,253	20