CONSOLIDATED STATEMENTS OF DEFICIT - USD ($)	12 Months Ended
	Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2023
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	$ (949,688,000)	$ (898,791,000)	$ (887,811,000)
Contributions in connection with non-cash ESOP compensation charges	3,143,000	3,234,000	2,935,000
Distributions		(1,010,000)
Distributions to Class B unitholders		(99,996,000)	(49,998,000)
Net earnings allocated to preferred units	(64,068,000)	(64,778,000)	(64,314,000)
Net (loss) earnings	(16,373,000)	110,677,000	137,621,000
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	(15,566,000)	110,216,000	136,881,000
Other comprehensive income (loss)	(2,142,000)	976,000	(37,224,000)
Partners' capital balance	(1,029,128,000)	(949,688,000)	(898,791,000)
Accumulated other comprehensive income
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	2,025,000	1,059,000	37,907,000
Other comprehensive income (loss)	(2,120,000)	966,000	(36,848,000)
Partners' capital balance	(95,000)	2,025,000	1,059,000
Parent
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	(941,989,000)	(891,598,000)	(880,224,000)
Contributions in connection with non-cash ESOP compensation charges	3,111,000	3,201,000	2,905,000
Distributions		0
Distributions to Class B unitholders		(99,996,000)	(49,998,000)
Net earnings allocated to Class B Units		0	0
Net earnings allocated to preferred units	(64,068,000)	(64,778,000)	(64,314,000)
Net (loss) earnings	(15,566,000)	110,216,000	136,881,000
Other comprehensive income (loss)	(2,120,000)	966,000	(36,848,000)
Partners' capital balance	(1,020,632,000)	(941,989,000)	(891,598,000)
Non-controlling interest
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	(7,699,000)	(7,193,000)	(7,587,000)
Contributions in connection with non-cash ESOP compensation charges	32,000	33,000	30,000
Distributions		(1,010,000)
Distributions to Class B unitholders		0	0
Net earnings allocated to Class B Units		0	0
Net earnings allocated to preferred units	0	0	0
Net (loss) earnings	(807,000)	461,000	740,000
Other comprehensive income (loss)	(22,000)	10,000	(376,000)
Partners' capital balance	(8,496,000)	$ (7,699,000)	$ (7,193,000)
Limited partner unitholders
Increase (Decrease) in Partners' Capital [Roll Forward]
Distributions	$ (250,000,000)
Limited partner unitholders | Class A Limited Partner Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance (in shares)	4,857,600	4,857,600	4,857,600
Partners' capital balance	$ (1,256,946,000)	$ (1,205,103,000)	$ (1,229,823,000)
Contributions in connection with non-cash ESOP compensation charges	3,080,000	3,169,000	2,876,000
Net earnings allocated to Class B Units		(99,996,000)	(49,998,000)
Net earnings allocated to preferred units	(63,427,000)	(64,130,000)	(63,671,000)
Net (loss) earnings	(15,411,000)	109,114,000	135,513,000
Partners' capital balance	$ (1,332,704,000)	$ (1,256,946,000)	$ (1,205,103,000)
Partners' capital balance (in shares)	4,857,600	4,857,600	4,857,600
Limited partner unitholders | Class B Limited Partner Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance (in shares)	1,300,000	1,300,000	1,300,000
Partners' capital balance	$ 383,012,000	$ 383,012,000	$ 383,012,000
Distributions to Class B unitholders		(99,996,000)	(49,998,000)
Net earnings allocated to Class B Units		99,996,000	49,998,000
Partners' capital balance	$ 383,012,000	$ 383,012,000	$ 383,012,000
Partners' capital balance (in shares)	1,300,000	1,300,000	1,300,000
General partner unitholders
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance (in shares)	49,500	49,500	49,500
Partners' capital balance	$ (70,080,000)	$ (70,566,000)	$ (71,320,000)
Contributions in connection with non-cash ESOP compensation charges	31,000	32,000	29,000
Net earnings allocated to preferred units	(641,000)	(648,000)	(643,000)
Net (loss) earnings	(155,000)	1,102,000	1,368,000
Partners' capital balance	$ (70,845,000)	$ (70,080,000)	$ (70,566,000)
Partners' capital balance (in shares)	49,500	49,500	49,500
Ferrellgas, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	$ (950,011,000)	$ (898,851,000)	$ (887,826,000)
Contributions in connection with non-cash ESOP compensation charges	3,143,000	3,234,000	2,935,000
Distributions		(101,010,000)	(50,000,000)
Net earnings allocated to preferred units	(64,068,000)	(64,778,000)	(64,314,000)
Net (loss) earnings	(15,841,000)	110,418,000	137,578,000
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	(15,841,000)	110,418,000	137,578,000
Other comprehensive income (loss)	(2,142,000)	976,000	(37,224,000)
Partners' capital balance	(1,028,919,000)	(950,011,000)	(898,851,000)
Ferrellgas, L.P. | Accumulated other comprehensive income
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	2,059,000	1,083,000	38,307,000
Other comprehensive income (loss)	(2,142,000)	976,000	(37,224,000)
Partners' capital balance	(83,000)	2,059,000	1,083,000
Ferrellgas, L.P. | Limited partner unitholders
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	(944,337,000)	(892,717,000)	(918,146,000)
Contributions in connection with non-cash ESOP compensation charges	3,111,000	3,201,000	2,905,000
Distributions		(100,000,000)	(50,000,000)
Net earnings allocated to preferred units	(64,068,000)	(64,778,000)	(64,314,000)
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	(15,034,000)	109,957,000	136,838,000
Partners' capital balance	(1,020,328,000)	(944,337,000)	(892,717,000)
Ferrellgas, L.P. | General partner unitholders
Increase (Decrease) in Partners' Capital [Roll Forward]
Partners' capital balance	(7,733,000)	(7,217,000)	(7,987,000)
Contributions in connection with non-cash ESOP compensation charges	32,000	33,000	30,000
Distributions		(1,010,000)
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	(807,000)	461,000	740,000
Partners' capital balance	(8,508,000)	(7,733,000)	(7,217,000)
Ferrellgas Partners Finance Corp
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) earnings	(366)	(636)	(1,015)
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	(366)	(636)	(1,015)
Ferrellgas Partners Finance Corp | Accumulated deficit
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) earnings attributable to Ferrellgas Partners, L.P.	$ (366)	$ (636)	$ (1,015)