Derivative instruments and hedging activities - AOCI Rollforward (Details) MMBbls in Millions	3 Months Ended
	Oct. 31, 2023 USD ($) MMBbls	Oct. 31, 2022 USD ($)
Derivative instruments and hedging activities
Partners' capital balance, beginning	$ (898,791,000)	$ (887,811,000)
Change in value of risk management commodity derivatives	(13,472,000)	(36,185,000)
Reclassification of losses (gains) on commodity hedges to cost of sales - propane and other gas liquids sales, net	3,184,000	(12,788,000)
Partners' capital balance, ending	(942,511,000)	(957,069,000)
Reclassification of net gain to earnings during next 12 months	8,800,000
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	2.7
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest [Member]
Derivative instruments and hedging activities
Partners' capital balance, beginning	$ 1,059,000	37,907,000
Change in value of risk management commodity derivatives	(13,472,000)	(36,185,000)
Reclassification of losses (gains) on commodity hedges to cost of sales - propane and other gas liquids sales, net	3,184,000	(12,788,000)
Less: amount attributable to noncontrolling interests	104,000	495,000
Partners' capital balance, ending	(9,125,000)	(10,571,000)
Ferrellgas, L.P
Derivative instruments and hedging activities
Partners' capital balance, beginning	(898,851,000)	(887,826,000)
Change in value of risk management commodity derivatives	(13,472,000)	(36,185,000)
Reclassification of losses (gains) on commodity hedges to cost of sales - propane and other gas liquids sales, net	3,184,000	(12,788,000)
Partners' capital balance, ending	(942,553,000)	(957,083,000)
Ferrellgas, L.P | Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest [Member]
Derivative instruments and hedging activities
Partners' capital balance, beginning	1,083,000	38,307,000
Change in value of risk management commodity derivatives	(13,472,000)	(36,185,000)
Reclassification of losses (gains) on commodity hedges to cost of sales - propane and other gas liquids sales, net	3,184,000	(12,788,000)
Partners' capital balance, ending	$ (9,205,000)	$ (10,666,000)