Goodwill And Intangible Assets, Net Goodwill And Intangible Assets, Net (Goodwill Rollforward) (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2017	Jul. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 256,103	$ 478,747
Goodwill acquisitions	0	1,358
Goodwill, Purchase Accounting Adjustments		(4,115)
Goodwill, Written off Related to Sale of Business Unit		(17)
Goodwill, Impairment Loss		(219,870)
Goodwill, ending balance	256,103	256,103
Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	256,103	478,747
Goodwill acquisitions	0	1,358
Goodwill, Purchase Accounting Adjustments		(4,115)
Goodwill, Written off Related to Sale of Business Unit		(17)
Goodwill, Impairment Loss		(219,870)
Goodwill, ending balance	256,103	256,103
Propane and related equipment sales [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	256,103	256,120
Goodwill acquisitions	0	0
Goodwill, Purchase Accounting Adjustments		0
Goodwill, Written off Related to Sale of Business Unit		(17)
Goodwill, Impairment Loss		0
Goodwill, ending balance	256,103	256,103
Propane and related equipment sales [Member] \| Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	256,103	256,120
Goodwill acquisitions	0	0
Goodwill, Purchase Accounting Adjustments		0
Goodwill, Written off Related to Sale of Business Unit		(17)
Goodwill, Impairment Loss		0
Goodwill, ending balance	256,103	256,103
Midstream - Crude Oil Logistics [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	0	222,627
Goodwill acquisitions	0	1,358
Goodwill, Purchase Accounting Adjustments		(4,115)
Goodwill, Written off Related to Sale of Business Unit		0
Goodwill, Impairment Loss		(190,554)
Goodwill, ending balance	0	0
Midstream - Crude Oil Logistics [Member] \| Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	0	222,627
Goodwill acquisitions	0	1,358
Goodwill, Purchase Accounting Adjustments		(4,115)
Goodwill, Impairment Loss		(190,600)
Goodwill, ending balance	$ 0	0
Maximum [Member] \| Midstream - Crude Oil Logistics [Member]
Goodwill [Roll Forward]
Goodwill, Impairment Loss		(219,870)
Maximum [Member] \| Midstream - Crude Oil Logistics [Member] \| Ferrellgas, L.P. [Member]
Goodwill [Roll Forward]
Goodwill, Impairment Loss		$ (219,870)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 350
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

+ References

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