Defined Contribution Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Defined Contribution Plans (Textual)
Maximum percentage of participants contribution	20.00%
Percentage of discretionary matching contributions	50.00%
Defined benefit plan compensation	6.00%
Company's cost for contributions to the plan	$ 1,200	$ 1,100	$ 1,200
Employment period contributions, description	First five years.