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Equity (Details) - USD ($)			1 Months Ended		2 Months Ended	12 Months Ended
	Aug. 02, 2018	Apr. 16, 2018	Dec. 21, 2018	May 31, 2018	Oct. 12, 2020	Jul. 31, 2020	Jul. 31, 2019
Equity (Details) [Line Items]
Aggregate purchase price (in Dollars)							$ 13,272,000
Noncontrolling Interest [Member]
Equity (Details) [Line Items]
Accumulated deficit (in Dollars)	$ 2,000,000.0
Stock Repurchases [Member] | Subsequent Event [Member]
Equity (Details) [Line Items]
Shares remained available for repurchase under the stock repurchase program					5,800,000
Common Class B [Member]
Equity (Details) [Line Items]
Aggregate repurchased shares						8,000,000.0
Shares remained available for repurchase under the stock repurchase program						6,200,000
Common Class B [Member] | Howard S. Jonas [Member]
Equity (Details) [Line Items]
Treasury shares of common stock sold			2,546,689
Aggregate consideration for sale of treasury shares (in Dollars)			$ 14,800,000
Closing price of Class B common stock (in Dollars per share)			$ 5.89
Aggregate purchase price (in Dollars)				$ 1,500,000
Purchase price reduced (in Dollars)		$ 200,000
Agreed to purchase shares of common stock		2,546,689
Common Class B [Member] | Employee [Member]
Equity (Details) [Line Items]
Class B common stock shares repurchased						37,348	3,748
Aggregate purchase price of shares repurchased (in Dollars)						$ 300,000	$ 28,000
Common Class B [Member] | Stock Repurchases [Member]
Equity (Details) [Line Items]
Class B common stock shares repurchased						671,117	729,110
Aggregate purchase price of shares repurchased (in Dollars)						$ 4,200,000	$ 3,900,000
Common Class B [Member] | Stock Repurchases [Member] | Subsequent Event [Member]
Equity (Details) [Line Items]
Class B common stock shares repurchased					463,792
Aggregate purchase price of shares repurchased (in Dollars)					$ 2,800,000
Common Class B [Member] | Stock Repurchases [Member] | Fiscal 2021 [Member]
Equity (Details) [Line Items]
Class B common stock shares repurchased						1

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