Goodwill And Intangible Assets, Net - Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 246,098
Impairment		$ (10,000)
Goodwill, ending balance	247,195	246,098
Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	246,098
Impairment		(10,000)
Goodwill, ending balance	247,195	246,098
Propane and related equipment sales
Goodwill [Roll Forward]
Goodwill, beginning balance	246,098	256,103
Goodwill acquisitions	(1,410)
Impairment		(10,005)
Other	(313)
Goodwill, ending balance	247,195	246,098
Propane and related equipment sales \| Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	246,098	256,103
Goodwill acquisitions	1,410
Impairment		(10,005)
Other	(313)
Goodwill, ending balance	$ 247,195	$ 246,098

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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