Fair value measurements - Assets and Liabilities (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Apr. 30, 2025	Jul. 31, 2024
Fair value measurements
Commodity derivatives propane swap assets	$ 3,889	$ 6,519
Commodity derivatives propane swap liabilities	(2,426)	(4,460)
Level 1
Fair value measurements
Commodity derivatives propane swap assets	0	0
Commodity derivatives propane swap liabilities	0	0
Level 2
Fair value measurements
Commodity derivatives propane swap assets	3,889	6,519
Commodity derivatives propane swap liabilities	(2,426)	(4,460)
Level 3
Fair value measurements
Commodity derivatives propane swap assets	0	0
Commodity derivatives propane swap liabilities	$ 0	$ 0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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