Goodwill and intangible assets, net - Lives (Details)	12 Months Ended
	Jul. 31, 2022
Minimum [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset useful life	2 years
Maximum [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset useful life	15 years
Customer Lists [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset, weighted average useful life	15 years
Customer Lists [Member] | Maximum [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset useful life	15 years
Non Compete Agreements And Other Intangible Assets [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset, weighted average useful life	9 years
Non Compete Agreements And Other Intangible Assets [Member] | Minimum [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset useful life	5 years
Non Compete Agreements And Other Intangible Assets [Member] | Maximum [Member]
Finite Lived And Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible asset useful life	10 years