Equity (Deficit) - Contributions and AOCI (Details) - USD ($)	3 Months Ended
Oct. 31, 2022	Oct. 31, 2021
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP compensation charges	$ 723,000	$ 909,000
General Partner
Capital Unit [Line Items]
Non-cash contribution	14,000.0	17,000.0
Contributions in connection with non-cash ESOP compensation charges	7,000	8,000
Ferrellgas, L.P
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP compensation charges	723,000	909,000
Ferrellgas, L.P \| Common Unitholders [Member]
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP compensation charges	716,000	900,000
Ferrellgas, L.P \| General Partner
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP compensation charges	$ 7,000.0	$ 9,000.0
Ferrellgas Inc., General Partner \| Ferrellgas, L.P
Capital Unit [Line Items]
General partner ownership interest		1.0101%
Ferrellgas Inc., General Partner \| Ferrellgas Partners LP
Capital Unit [Line Items]
General partner ownership interest	1.00%

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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