Supplemental Financial Statement Information Supplemental Financial Statement Information (Loss on Asset Sales and Disposal) (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2016	Oct. 31, 2015
Loss on Disposal of Assets and Asset Impairment Charges	$ 6,423	$ 14,917
Impairment of Long-Lived Assets to be Disposed of	0	12,112
Assets held for disposal [Member]
Gain (Loss) on Disposition of Property Plant Equipment	0	1,259
Assets held in use [Member]
Gain (Loss) on Disposition of Property Plant Equipment	6,423	1,546
Ferrellgas, L.P. [Member]
Loss on Disposal of Assets and Asset Impairment Charges	6,423	14,917
Impairment of Long-Lived Assets to be Disposed of	0	12,112
Ferrellgas, L.P. [Member] \| Assets held for disposal [Member]
Gain (Loss) on Disposition of Property Plant Equipment	0	1,259
Ferrellgas, L.P. [Member] \| Assets held in use [Member]
Gain (Loss) on Disposition of Property Plant Equipment	$ 6,423	$ 1,546

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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- Definition

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

+ References

No definition available.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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