Partners' Deficit - Contributions and AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2020	Oct. 31, 2019
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	$ 708	$ 795
Common Unitholders [Member]
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	694	779
General Partner [Member]
Capital Unit [Line Items]
Non-cash contribution	14	16,000
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	7	8
Ferrellgas, L.P. [Member]
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	708	795
Ferrellgas, L.P. [Member] \| Common Unitholders [Member]
Capital Unit [Line Items]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	701	787
Ferrellgas, L.P. [Member] \| General Partner [Member]
Capital Unit [Line Items]
Non-cash contribution	7	8,000
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	$ 7	$ 8
Ferrellgas Inc., General Partner [Member] \| Ferrellgas, L.P. [Member]
Capital Unit [Line Items]
General partner ownership interest	1.0101%	1.0101%
Ferrellgas Inc., General Partner [Member] \| Ferrellgas Partners LP [Member]
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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-Name Accounting Standards Codification
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