Summary of Significant Accounting Policies (Details)	12 Months Ended
	Jul. 31, 2020
Accounting Policies [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Method Used	The fair value of each option, without a market-based condition was estimated on the measurement date using the Black-Scholes Merton (“BSM”) option-pricing model. For options that included a market-based condition the Monte Carlo simulation model was used. The Black-Scholes Merton option-pricing model utilized the following assumptions:July 31,202020192018Expected life (in years)5.4—5.75.3—6.65.3—6.9Risk-free interest rate0.29 %—1.67 %1.80 %—2.69 %1.88 %—2.62 %Estimated volatility21.7%—27.6%21.6%—22.1%19.7%—20.7%Expected dividends— %— %— %Weighted average fair value at measurement date$21.54 $15.47 $8.88