Revenue from contracts with customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2024	Apr. 30, 2023	Jul. 31, 2023
Revenue from contracts with customers
Total revenues	$ 515,774	$ 587,347	$ 1,496,664	$ 1,684,579
Contract assets and liabilities
Contract assets	13,315		13,315		$ 10,263
Contract liabilities
Deferred revenue	$ 42,305		42,305		$ 51,516
Deferred revenue recognized			$ 36,900
Maximum | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-11-01
Contract liabilities
Remaining performance obligation recognition period	1 year		1 year
Propane and related equipment revenues
Revenue from contracts with customers
Total revenues	$ 515,774	587,347	$ 1,496,664	1,684,579
Retail - Sales to End Users
Revenue from contracts with customers
Total revenues	367,300	431,538	1,033,000	1,195,961
Wholesale - Sales to Resellers
Revenue from contracts with customers
Total revenues	119,739	123,532	368,088	388,154
Other Gas Sales
Revenue from contracts with customers
Total revenues	3,018	3,977	12,112	12,662
Other
Revenue from contracts with customers
Total revenues	$ 25,717	$ 28,300	$ 83,464	$ 87,802