Partnership Organization And Formation (Details) shares in Millions	6 Months Ended
Jan. 31, 2019 subsidiary shares	Jan. 31, 2018
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Number of subsidiaries \| subsidiary	2
Number of states in which entity operates	50
Ferrellgas, L.P. [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
General partner ownership interest	1.0101%	1.0101%
Number of states in which entity operates	50
Ferrellgas [Member] \| Ferrellgas Inc., General Partner [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
General partner ownership interest	2.00%	2.00%
Ferrellgas Partners LP [Member] \| Ferrell Companies [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Common stock shares outstanding \| shares	22.8
Ferrellgas Partners LP [Member] \| Ferrellgas Inc., General Partner [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
General partner ownership interest	1.00%
Ferrellgas, L.P. [Member] \| Ferrellgas Partners LP [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Limited partner interest	99.00%
Ferrellgas, L.P. [Member] \| Ferrellgas Inc., General Partner [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
General partner ownership interest	1.00%
Ferrellgas Partners Finance Corp. [Member] \| Ferrellgas Partners LP [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership Percentage	100.00%
Ferrellgas Finance Corp. [Member] \| Ferrellgas, L.P. [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership Percentage	100.00%

Number Of Entity Subsidiaries

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

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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

No definition available.

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- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010

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