Contingencies And Commitments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Accrual for litigation expenses	$ 10.0
Ferrellgas, L.P. And Subsidiaries [Member] \| Property And Equipment [Member]
Non-cancelable operating leases, expiration year	2024
Rental expense	33.3	33.7	38.6
Property And Equipment [Member]
Non-cancelable operating leases, expiration year	2024
Rental expense	33.3	33.7	38.6
Ferrellgas, L.P. And Subsidiaries [Member] \| Transportation Equipment [Member]
Transportation equipment lease expiration period, years	7
Fair value of these residual value guarantees	0.8
Residual value of leased assets	4.4
Transportation Equipment [Member]
Transportation equipment lease expiration period, years	7
Fair value of these residual value guarantees	0.8
Residual value of leased assets	4.4
Ferrellgas, L.P. And Subsidiaries [Member]
Accrual for litigation expenses	$ 10.0

Guarantees residual value, Fair value disclosure

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- Definition

Non-cancelable operating leases, expiration year

+ Details

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- Definition

Transportation Equipment Lease Expiration Period Years

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- Definition

The estimate of the value of the leased asset at the end of the lease term.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 43
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 30
-Paragraph 14
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6791857&loc=d3e42840-112730

+ Details

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

+ Details

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