Equity (Details) - USD ($) $ / shares in Units, $ in Thousands						1 Months Ended		12 Months Ended
	Dec. 21, 2018	Jun. 09, 2017	May 01, 2017	Apr. 11, 2017	Apr. 10, 2017	May 31, 2018	Apr. 16, 2018	Aug. 01, 2019	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Equity (Textual)
Voting rights description									The holders of Class A common stock are entitled to three votes per share and the holders of Class B common stock are entitled to one-tenth of a vote per share.
Aggregate purchase price									$ 13,272		$ 24,930
Common Stock [Member]
Equity (Textual)
Total cash dividends paid										$ 13,900	$ 17,900
Aggregate cash dividends paid per share										$ 0.56	$ 0.76
Noncontrolling Interest [Member]
Equity (Textual)
Accumulated deficit								$ 2,000	$ (2,002)
Howard S. Jonas [Member]
Equity (Textual)
Aggregate purchase price						$ 1,500
Common Class B [Member]
Equity (Textual)
Repurchase of aggregate shares									8,000,000
Shares remained available for repurchase under the stock repurchase program									6,900,000
Treasury shares									908,000	2,722,000
Common Class B [Member] | Stock Repurchases [Member]
Equity (Textual)
Class B common stock shares repurchased									729,110	367,484
Aggregate purchase price of shares repurchased									$ 3,900	$ 1,900
Common Class B [Member] | Employee [Member]
Equity (Textual)
Class B common stock shares repurchased									3,748	57,081	94,338
Aggregate purchase price of shares repurchased									$ 28,000	$ 400	$ 1,800
Common Class B [Member] | Howard S. Jonas [Member]
Equity (Textual)
Treasury shares of common stock sold				728,332
Closing price of Class B common stock			$ 14.93		$ 13.73
Aggregate consideration for sale of treasury shares				$ 10,000
Aggregate purchase price	$ 14,800
Agreed to purchase shares of common stock	2,546,689	1,000,000					2,546,689
Aggregate consideration		$ 14,900
Class B common stock at a price per share							$ 5.89
Purchase price reduced							$ 200