Supplemental financial statement information - Inventories (Details) $ in Thousands, gal in Millions	12 Months Ended
Jul. 31, 2025 USD ($) gal	Jul. 31, 2024 USD ($)
Supplemental financial statement information
Propane gas and related products	$ 66,052	$ 74,122
Appliances, parts and supplies, and other	21,755	21,910
Inventories	$ 87,807	$ 96,032
Supply procurement contract duration	36 months
Net procurement of fixed priced propane by Ferrellgas in gallons \| gal	3.0

Maximum Period Of Inventory Procurement Fixed Price

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- Definition

Supplemental Financial Statement Information [Abstract]

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- Definition

Quantity of oil and gas subject to delivery commitment under existing contract or agreement stated in unit of measurement, including, but not limited to, barrel for oil and synthetic oil or cubic feet for natural and synthetic gas.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Regulation S-K (SK)
-Number 229
-Section 1207
-Paragraph a
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-Publisher SEC

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- Definition

Carrying amount as of the balance sheet date of product derived from petroleum during the processing of oil or natural gas which is then used as a heat source or fuel.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount, after of valuation reserves and allowances, of inventory, classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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