Summary of significant accounting policies (Details) $ in Thousands		12 Months Ended
Mar. 16, 2026 shares	Jul. 31, 2026 USD ($) subsidiary item
Summary of significant accounting policies
Number of reporting units \| item		1
Goodwill impairment recognized \| $		$ 0
Reporting unit, percentage of fair value in excess of carrying amount		169.00%
Accounts receivable collection period		30 days
Revenue recognized over a straight-line basis, term		1 year
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
Number of taxable subsidiaries		1
Class B Limited Partner Units
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
Converted outstanding Class B Units into Class A Units \| shares	1,300,000
Ferrellgas Partners LP \| Non-Controlling Interest
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
General partner ownership interest		1.00%
Minimum [Member]
Summary of significant accounting policies
Property, plant and equipment useful life		2 years
Intangible asset useful life		5 years
Maximum [Member]
Summary of significant accounting policies
Property, plant and equipment useful life		30 years
Intangible asset useful life		15 years
Ferrellgas, L.P.
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
Number of taxable subsidiaries		3

The period of time during which amounts receivable are collected.

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Number of taxable subsidiaries.

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Revenue Recognized Over Straight Line Basis, Term

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Significant Accounting Policies [Line Items]

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Useful life of finite-lived intangible asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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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).

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Useful life of property, plant, and equipment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection.

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Percentage of fair value of reporting unit in excess of carrying amount.

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