Revenue - Narrative (Details) - USD ($)	9 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Revenue from Contract with Customer [Abstract]
Contract assets, increase due to business combinations	$ 824,000
Contract liabilities, increase due to business combinations	6,208,000
Revenue recognized	31,000,000	$ 30,061,000
Remaining performance obligation, amount	$ 640,702,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-05-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated period to satisfy a substantial portion of remaining performance obligations	24 months