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Stock-Based Compensation (Details) - USD ($)					1 Months Ended	12 Months Ended
	Jan. 06, 2020	Jan. 06, 2020	Dec. 12, 2019	Dec. 13, 2018	Sep. 30, 2020	Jul. 31, 2020	Jul. 31, 2019
Stock-Based Compensation (Details) [Line Items]
Option term, description						Share awards generally vest on a graded basis over three years of service.
Common stock shares issued for vested (in Shares)						100,000
Subsequent Event [Member]
Stock-Based Compensation (Details) [Line Items]
Business unit					$ 100,000,000
Stock Options [Member]
Stock-Based Compensation (Details) [Line Items]
Total intrinsic value of options exercised during the period						$ 16,000
Restricted Stock [Member]
Stock-Based Compensation (Details) [Line Items]
Total unrecognized non-vested stock-based compensation						$ 500,000
Non-vested stock options, weighted-average period						9 months 18 days
Total grant date fair value						$ 300,000	$ 700,000
Deferred Stock Units [Member]
Stock-Based Compensation (Details) [Line Items]
Total unrecognized non-vested stock-based compensation						$ 1,300,000
Non-vested stock options, weighted-average period						8 months 12 days
Total grant date fair value						$ 1,100,000
Deferred Stock Units [Member]
Stock-Based Compensation (Details) [Line Items]
Delayed vesting shares (in Shares)		38,024
Common Class B [Member]
Stock-Based Compensation (Details) [Line Items]
Additional shares available stock option incentive plan for grants (in Shares)			400,000	100,000
Shares of common stock reserved for award under 2015 stock option and incentive plan (in Shares)						1,600,000
Shares of common stock available for future grants (in Shares)						600,000
Common stock shares issued for vested (in Shares)						32,000
Common Class B [Member] | Deferred Stock Units [Member]
Stock-Based Compensation (Details) [Line Items]
Vesting date, description						the DSUs will vest in three equal amounts on each of January 6, 2020, January 5, 2021, and January 5, 2022. The number of shares that will be issuable on each vesting date will vary between 50% to 200% of the number of DSUs that vest on that vesting date, depending on the market price for the underlying Class B common stock on the vesting date relative to the market price at the time of the grant.
Common Class B [Member] | Deferred Stock Units [Member]
Stock-Based Compensation (Details) [Line Items]
Common stock shares issued for vested (in Shares)	100,284

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