Transactions with related parties (Details) $ in Thousands	3 Months Ended
Oct. 31, 2023 USD ($) employee	Oct. 31, 2022 USD ($)
Transactions with related parties
Number of employees \| employee	0
Ferrellgas Inc., General Partner
Transactions with related parties
Operating expense	$ 76,859	$ 68,982
General and administrative expense	$ 9,329	$ 7,870

Amount of expense for investment management fee, including, but not limited to, expense in connection with research, selection, supervision, and custody of investment.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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