Acquisitions and dispositions - Fair Value Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Goodwill, Name of Segment [Extensible List]	Propane and related equipment sales [Member]
Goodwill	$ 257,099	$ 246,946	$ 247,195
Series of Individually Immaterial Business Acquisitions [Member] \| Propane and related equipment sales [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Customer tanks, buildings, land and other	6,564	2,607	6,598
Goodwill	10,153
Aggregate fair value of net assets acquired	21,701	7,911	11,170
Series of Individually Immaterial Business Acquisitions [Member] \| Propane and related equipment sales [Member] \| Customer Lists [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Finite-lived Intangible Assets Acquired	4,259	4,973	738
Series of Individually Immaterial Business Acquisitions [Member] \| Propane and related equipment sales [Member] \| Non-Compete Agreements [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Finite-lived Intangible Assets Acquired	725	331	$ 3,834
Ferrellgas, L.P. [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Goodwill	$ 257,099	$ 246,946

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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