Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Oct. 31, 2017	Oct. 31, 2016
Shares excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted loss per share	371	121
Warrants [Member]
Shares excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted loss per share	60
Non-vested restricted Class B common stock [Member]
Shares excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted loss per share	269	118
Stock options [Member]
Shares excluded from the diluted earnings per share computations
Shares excluded from the calculation of diluted loss per share	42	3