Partners' Deficit - Ownership (Details) - shares	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018
Capital Unit [Line Items]
Common unitholders, units outstanding	97,152,665	97,152,665
Minimum percentage ownership of outstanding common units resulting in non voting of owners	20.00%
Ferrell Companies [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	22,529,361	22,529,361
James E. Ferrell [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	4,763,475	4,763,475
Ferrellgas Partners LP [Member]
Capital Unit [Line Items]
Limited partner ownership interest	98.00%
General partner ownership interest	2.00%	2.00%
Ferrellgas Partners LP [Member] \| Ferrell Companies [Member]
Capital Unit [Line Items]
Limited partner ownership interest	23.40%
Ferrell Companies [Member] \| Ferrellgas Partners LP [Member]
Capital Unit [Line Items]
Limited partner ownership interest	23.20%
Ferrell Companies [Member] \| Ferrellgas, L.P. [Member]
Capital Unit [Line Items]
General partner ownership interest	1.00%
FCI Trading Corp. [Member] \| Ferrell Companies [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	195,686
Ferrell Propane, Inc. [Member] \| Ferrell Companies [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	51,204
JEF Capital Management [Member] \| James E. Ferrell [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	4,758,859
Ferrell Resources Holdings, Inc. [Member] \| Ferrellgas Partners LP [Member] \| James E. Ferrell [Member]
Capital Unit [Line Items]
Common unitholders, units outstanding	4,616
Ferrellgas, L.P. [Member] \| Ferrellgas Partners LP [Member]
Capital Unit [Line Items]
General partner ownership interest	1.00%
Ferrellgas Inc., General Partner [Member] \| Ferrellgas Partners LP [Member]
Capital Unit [Line Items]
General partner ownership interest	1.00%
Ferrellgas Inc., General Partner [Member] \| Ferrellgas, L.P. [Member]
Capital Unit [Line Items]
General partner ownership interest	1.0101%	1.0101%

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- Definition

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.

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

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- Definition

The number of limited partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

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