Derivative instruments and hedging activities - Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2026	Jul. 31, 2025
Derivative instruments and hedging activities
Gain (loss) recognized due to ineffectiveness	$ 0	$ 0
Total Asset Derivatives	5,370	3,570
Total Liability Derivatives	9,468	3,654
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Derivative instruments and hedging activities
Commodity derivatives-propane swap assets	310	326
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Derivative instruments and hedging activities
Commodity derivatives-propane swap liabilities	8,864	3,306
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Derivative instruments and hedging activities
Commodity derivatives-propane swap liabilities	604	348
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Derivative instruments and hedging activities
Commodity derivatives-propane swap assets	$ 5,060	$ 3,244

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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