Segments and Other Geographic Reporting (Details) $ in Thousands	3 Months Ended
	Oct. 31, 2021 USD ($) Segment	Oct. 31, 2020 USD ($)	Jul. 31, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | Segment	2
Number of reportable segments | Segment	2
Service revenues and vehicle sales	$ 810,132	$ 592,940
Yard operations	298,694	231,811
Cost of vehicle sales	126,408	64,360
General and administrative	54,909	48,175
Operating income	330,121	248,594
Depreciation and amortization	31,760	28,949
Capital expenditures and acquisitions	64,696	147,093
Total assets	4,918,852		$ 4,562,143
Goodwill	354,062		355,717
Operating Segments | US | United States
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	678,461	497,255
Yard operations	256,621	194,419
Cost of vehicle sales	80,342	41,506
General and administrative	46,548	39,738
Operating income	294,949	221,591
Depreciation and amortization	27,725	26,162
Capital expenditures and acquisitions	54,272	122,459
Total assets	4,223,448		3,900,712
Goodwill	270,269		270,305
Operating Segments | International | International
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	131,671	95,685
Yard operations	42,073	37,392
Cost of vehicle sales	46,066	22,854
General and administrative	8,361	8,437
Operating income	35,172	27,003
Depreciation and amortization	4,035	2,787
Capital expenditures and acquisitions	10,424	24,634
Total assets	695,404		661,431
Goodwill	83,793		$ 85,412
Service revenues
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	667,818	515,372
Service revenues | Operating Segments | US | United States
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	590,758	450,235
Service revenues | Operating Segments | International | International
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	77,060	65,137
Vehicle sales
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	142,314	77,568
Vehicle sales | Operating Segments | US | United States
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	87,703	47,020
Vehicle sales | Operating Segments | International | International
Segment Reporting Information [Line Items]
Service revenues and vehicle sales	$ 54,611	$ 30,548