Debt Debt (Consolidated Fixed Charge Coverage Ratio) (Details) - $ / shares	3 Months Ended	12 Months Ended
Jul. 31, 2017	Jul. 31, 2017	Jul. 31, 2016
Required fixed charge coverage ratio		175.00%
Current fixed charge coverage ratio		150.00%
Debt Instrument, Covenant Compliance		67.5
Debt Instrument, Covenant Description		8.7
Distribution Made to Limited Partner, Distributions Declared, Per Unit	$ 0.10	$ 0.40	$ 2.05
Fixed Charge Coverage Covenant [Member]
Debt Instrument, Covenant Compliance	9.8
Debt Instrument, Restrictive Covenants		50.0
Debt Instrument, Covenant Description	40.2
Ferrellgas, L.P. [Member]
Debt Instrument, Covenant Compliance		67.5
Debt Instrument, Covenant Description		8.7

Current fixed charge coverage ratio

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- Definition

Required fixed charge coverage ratio

+ References

No definition available.

+ Details

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

+ Details

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- Definition

Description of covenants that limit or prohibit certain actions or activities without the lender's prior consent within a specified period of time or until certain specified targets are achieved for example, reduction of the debt or an increase in net worth to a specified amount).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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