Derivative instruments and hedging activities - AOCI Rollforward (Details) $ in Thousands, MMBbls in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2025 USD ($)	Apr. 30, 2024 USD ($)	Apr. 30, 2025 USD ($) MMBbls	Apr. 30, 2024 USD ($)
Derivative instruments and hedging activities
Partners' capital balance	$ (1,021,649)	$ (844,654)	$ (949,688)	$ (898,791)
Change in value of risk management commodity derivatives	(2,674)	(1,180)	7,081	(116)
Reclassification of losses on commodity hedges to cost of sales - propane and other gas liquids sales, net	(5,512)	(5,179)	(7,677)	75
Partners' capital balance	(985,107)	(914,046)	(985,107)	(914,046)
Reclassification of net gain to earnings during next 12 months			2,100
Gain (loss) on discontinuation of cash flow hedge due to forecasted transaction probable of not occurring, net			$ 0	0
Number of barrels of propane covered by cash flow hedges \| MMBbls			2.1
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Derivative instruments and hedging activities
Partners' capital balance			$ 2,059	1,083
Change in value of risk management commodity derivatives			7,081	(116)
Reclassification of losses on commodity hedges to cost of sales - propane and other gas liquids sales, net			(7,677)	75
Partners' capital balance	1,463	1,042	1,463	1,042
Ferrellgas, L.P.
Derivative instruments and hedging activities
Partners' capital balance	(1,021,981)	(844,698)	(950,011)	(898,851)
Change in value of risk management commodity derivatives	(2,674)	(1,180)	7,081	(116)
Reclassification of losses on commodity hedges to cost of sales - propane and other gas liquids sales, net	(5,512)	(5,179)	(7,677)	75
Partners' capital balance	(985,387)	(914,369)	(985,387)	(914,369)
Ferrellgas, L.P. \| Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Derivative instruments and hedging activities
Partners' capital balance			2,025	1,059
Change in value of risk management commodity derivatives			7,081	(116)
Reclassification of losses on commodity hedges to cost of sales - propane and other gas liquids sales, net			(7,677)	75
Less: amount attributable to noncontrolling interests			(6)
Partners' capital balance	$ 1,435	$ 1,018	$ 1,435	$ 1,018

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness, attributable to noncontrolling interest.

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of partners' capital (deficit), including portions attributable to both the parent and noncontrolling interests. Excludes temporary equity and is sometimes called permanent equity.

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