Description of Business and Summary of Significant Accounting Policies (Details 1) - shares shares in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share	345	199	335
Warrants [Member]
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share	65
Class B Common Stock
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share	7	88
Class B Common Stock | Non-vested restricted Class B common stock
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share
Class B Common Stock | Warrants [Member]
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share	7
Stock options [Member]
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share	29	3	4
Stock options [Member] | Class B Common Stock
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Shares excluded from the calculations of diluted loss per share		88