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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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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Indicates business segment in which reporting unit is included.

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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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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) $ in Thousands	3 Months Ended	12 Months Ended
	Jan. 31, 2018 USD ($)	Jul. 31, 2019 USD ($) subsidiary item shares	Jul. 31, 2018 USD ($)	Jul. 31, 2017 USD ($)
Significant Accounting Policies [Line Items]
Asset impairments	$ 10,000	$ 0	$ 10,005	$ 0
Number of reporting units \| item		2
Number of reporting units subject to assessment \| item		1
Goodwill impairment recognized			$ 10,000
Reporting Unit, Name of Segment [Extensible List]			Propane Operations And Related Equipment Sales Segment [Member]
Accounts receivable collection period		30 days
Revenue recognized over a straight-line basis, term		1 year
Non-cash stock and unit-based compensation charge		$ 0	$ 0	3,298
Number of taxable subsidiaries \| subsidiary		1
Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Asset impairments		$ 0	10,005	0
Goodwill impairment recognized			10,000
Accounts receivable collection period		30 days
Revenue recognized over a straight-line basis, term		1 year
Non-cash stock and unit-based compensation charge		$ 0	$ 0	3,298
Number of taxable subsidiaries \| subsidiary		3
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%
Ferrellgas Partners LP [Member] \| Ferrellgas, L.P. [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
Minimum [Member] \| Ferrellgas, L.P. [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
Maximum [Member] \| Ferrellgas, L.P. [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]
Significant Accounting Policies [Line Items]
Number of shares authorized to be issued as options \| shares		9,250,000
Non-cash stock and unit-based compensation charge		$ 0	$ 0	3,300
Ferrell Companies, Inc. Incentive Compensation Plan [Member] \| Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Number of shares authorized to be issued as options \| shares		9,250,000
Non-cash stock and unit-based compensation charge				$ 3,300
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member]
Significant Accounting Policies [Line Items]
Stock options, percent to vest upon event		100.00%
Retirement age		65
Award expiration period		10 years
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member] \| Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Stock options, percent to vest upon event		100.00%
Retirement age		65
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member] \| Minimum [Member]
Significant Accounting Policies [Line Items]
Award vesting period		0 years
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member] \| Minimum [Member] \| Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
Award vesting period		0 years
Award expiration period		10 years
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member] \| Maximum [Member]
Significant Accounting Policies [Line Items]
Award vesting period		10 years
Ferrell Companies Inc Deferred Incentive Compensation Plan [Member] [Member] \| Maximum [Member] \| Ferrellgas, L.P. [Member]
Significant Accounting Policies [Line Items]
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