The period of time during which amounts receivable are collected.

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Number of taxable subsidiaries

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Retirement Age

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Revenue Recognized Over Straight Line Basis, Term

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Fair value of share-based awards outstanding at balance sheet date. These are awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Share-based Compensation Arrangement by Share-based Payment Award, Percentage Of Award To Vest On Event

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Significant Accounting Policies [Line Items]

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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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 long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Number of reporting units with zero or negative amount of net assets.

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Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of shares authorized for issuance under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Summary Of Significant Accounting Policies (Narrative) (Details)	3 Months Ended	12 Months Ended
	Jan. 31, 2018 USD ($)	Jul. 31, 2020 USD ($) subsidiary item shares	Jul. 31, 2019 USD ($)	Jul. 31, 2018 USD ($)
Significant Accounting Policies [Line Items]
Asset impairments	$ 10,000,000	$ 0	$ 0	$ 10,005,000
Number of reporting units \| item		2
Number of reporting units subject to assessment \| item		1
Goodwill impairment recognized		$ 0
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 \| subsidiary		1
Ferrellgas Partners LP [Member]
Significant Accounting Policies [Line Items]
General partner ownership interest		2.00%	2.00%
Ferrellgas Partners LP [Member] \| Non-Controlling Interest [Member]
Significant Accounting Policies [Line Items]
General partner ownership interest		1.00%
Minimum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful life		2 years
Intangible asset useful life		2 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful life		30 years
Intangible asset useful life		15 years
Ferrell Companies, Inc. Incentive Compensation Plan [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Non-cash stock and unit-based compensation charge		$ 0	$ 0	0
Awards granted during the period \| shares		0
Awards outstanding, fair value		$ 0
Number of shares authorized to be issued \| shares		9,250,000
Stock options, percent to vest upon event		100.00%
Retirement age		65
Award expiration period		10 years
Ferrell Companies, Inc. Incentive Compensation Plan [Member] \| Minimum [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Award vesting period		0 years
Ferrell Companies, Inc. Incentive Compensation Plan [Member] \| Maximum [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Award vesting period		10 years
Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Number of reporting units \| item		2
Number of reporting units subject to assessment \| item		1
Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Asset impairments	$ 10,000,000			10,005,000
Goodwill impairment recognized		$ 0
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 \| subsidiary		3
Ferrellgas, L.P. [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful life		2 years
Intangible asset useful life		2 years
Ferrellgas, L.P. [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Property, plant and equipment useful life		30 years
Intangible asset useful life		15 years
Ferrellgas, L.P. [Member] \| Ferrell Companies, Inc. Incentive Compensation Plan [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Non-cash stock and unit-based compensation charge		$ 0	$ 0	$ 0
Awards granted during the period \| shares		0
Awards outstanding, fair value		$ 0
Number of shares authorized to be issued \| shares		9,250,000
Stock options, percent to vest upon event		100.00%
Retirement age		65
Ferrellgas, L.P. [Member] \| Ferrell Companies, Inc. Incentive Compensation Plan [Member] \| Minimum [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Award vesting period		0 years
Award expiration period		10 years
Ferrellgas, L.P. [Member] \| Ferrell Companies, Inc. Incentive Compensation Plan [Member] \| Maximum [Member]
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Award vesting period		10 years