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Derivative Instruments and Hedging Activities - Balance Sheet (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2022	Oct. 31, 2021	Jul. 31, 2022
Derivatives, Fair Value [Line Items]
Gain (loss) recognized due to ineffectiveness	$ 0	$ 0
Derivative Asset, Fair Value, Gross Asset	27,614		$ 51,267
Derivative Liability, Fair Value, Gross Liability	38,280		12,960
Price risk management asset
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	24,944		43,015
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	36,269		11,840
Other Assets, Net [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	2,670		8,252
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	$ 2,011		$ 1,120