Fair value measurements (Tables)

12 Months Ended

Jul. 31, 2025

Fair value measurements

Schedule of financial assets and liabilities measured at fair value on a recurring basis

	Asset (Liability)
	Quoted Prices in Active
	Markets for Identical		Significant Other
	Assets and Liabilities		Observable Inputs		Unobservable Inputs
	(Level 1)		(Level 2)		(Level 3)		Total
July 31, 2025:
Assets:
Derivative financial instruments:
Commodity derivatives	$	—	$	3,570	$	—	$	3,570
Liabilities:
Derivative financial instruments:
Commodity derivatives	$	—	$	(3,654)	$	—	$	(3,654)
July 31, 2024:
Assets:
Derivative financial instruments:
Commodity derivatives	$	—	$	6,519	$	—	$	6,519
Liabilities:
Derivative financial instruments:
Commodity derivatives	$	—	$	(4,460)	$	—	$	(4,460)