Partnership organization and formation (Details)	12 Months Ended
Jul. 31, 2025 USD ($) employee state subsidiary shares
Partnership organization and formation
Number of subsidiaries \| subsidiary	2
Number of employees	0
Ferrellgas Partners LP
Partnership organization and formation
General partner ownership interest	2.00%
Ferrellgas, L.P.
Partnership organization and formation
Number of states in which entity operates \| state	50
Ferrellgas Partners LP \| Ferrellgas, L.P.
Partnership organization and formation
Limited partner interest	99.00%
Ferrellgas Partners LP \| Ferrellgas Partners Finance Corp
Partnership organization and formation
Ownership percentage	100.00%
Ferrell Companies \| Ferrellgas Partners LP \| Class A Limited Partner Units
Partnership organization and formation
Ownership percentage	23.40%
Ferrellgas Inc., General Partner \| Ferrellgas
Partnership organization and formation
General partner ownership interest	2.00%
Ferrellgas Inc., General Partner \| Ferrellgas Partners LP
Partnership organization and formation
General partner ownership interest	1.00%
Ferrellgas Inc., General Partner \| Ferrellgas, L.P.
Partnership organization and formation
General partner ownership interest	1.0101%
Ferrellgas, L.P. \| Ferrellgas Finance Corp
Partnership organization and formation
Ownership percentage	100.00%
Ferrellgas Partners Finance Corp
Partnership organization and formation
Corporation formation proceeds from partnership \| $	$ 1,000
Corporation formation shares granted to partnership \| shares	1,000
Number of employees	0
Ferrellgas Finance Corp
Partnership organization and formation
Corporation formation proceeds from partnership \| $	$ 1,000
Corporation formation shares granted to partnership \| shares	1,000
Number of employees	0
Ferrellgas Employee Stock Ownership Trust \| Ferrell Companies
Partnership organization and formation
Ownership percentage	100.00%

Number of persons employed by the Entity

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Namespace Prefix:	dei_
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Balance Type:	na
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- Definition

Amount represents the contributions received from the partnership related to forming the corporation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount represents the number of shares granted to the partnership related to forming the corporation.

+ References

No definition available.

+ Details

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- Definition

Number Of Entity Subsidiaries

+ References

No definition available.

+ Details

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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
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482987/272-10-50-3

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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