Supplemental financial statement information - Inventories (Details) $ in Thousands, gal in Millions	3 Months Ended
Oct. 31, 2022 USD ($) gal	Jul. 31, 2022 USD ($)
Supplemental financial statement information
Propane gas and related products	$ 101,991	$ 96,679
Appliances, parts and supplies, and other	18,154	18,508
Inventories	$ 120,145	$ 115,187
Supply procurement contract duration	36 months
Net procurement of fixed priced propane by Ferrellgas in gallons \| gal	6.3

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.

+ References

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