Accrued interest paid on senior notes.

Name:	fgp_AccruedInterestOnSeniorNotePaid
Namespace Prefix:	fgp
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument, make whole payment

+ Details

Name:	fgp_DebtInstrumentMakeWholePayment
Namespace Prefix:	fgp
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Offering Price, Percent Of Par Value

+ Details

Name:	fgp_DebtInstrumentOfferingPricePercentOfParValue
Namespace Prefix:	fgp
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, principal amount redeemed

+ Details

Name:	fgp_DebtInstrumentPrincipalAmountRedeemed
Namespace Prefix:	fgp
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt maturity year

+ Details

Name:	fgp_DebtMaturityYear
Namespace Prefix:	fgp
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	instant

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 21
-Paragraph 16, 20
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument was issued, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

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 210.5-02.22(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentIssuanceDate
Namespace Prefix:	us-gaap
Data Type:	us-types:dateStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 26
-Paragraph 20, 21
-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 3: 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=6943989&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 19
-Subparagraph b
-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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfUnsecuredDebt
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28
-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 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

+ Details

Name:	us-gaap_WriteOffOfDeferredDebtIssuanceCost
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Debt (Senior Notes Narrative) (Details) (USD $)	1 Months Ended		12 Months Ended			1 Months Ended			1 Months Ended			1 Months Ended			1 Months Ended					1 Months Ended						1 Months Ended		12 Months Ended
Debt (Senior Notes Narrative) (Details) (USD $)	Apr. 30, 2010	Oct. 31, 2009	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 6.50%, Due 2021 [Member]	Nov. 30, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 6.50%, Due 2021 [Member]	Nov. 24, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 6.50%, Due 2021 [Member]	Jul. 31, 2011 Fixed Rate, 6.50%, Due 2021 [Member]	Nov. 30, 2010 Fixed Rate, 6.50%, Due 2021 [Member]	Nov. 24, 2010 Fixed Rate, 6.50%, Due 2021 [Member]	Nov. 30, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 6.75%, Due 2014 [Member]	Nov. 30, 2010 Fixed Rate, 6.75%, Due 2014 [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 8.625%, Due 2020 [Member]	Mar. 31, 2011 Fixed Rate, 8.625%, Due 2020 [Member]	Jul. 31, 2011 Fixed Rate, 8.625%, Due 2020 [Member]	Apr. 30, 2010 Fixed Rate, 8.625%, Due 2020 [Member]	Aug. 31, 2009 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 8.87% Series C Senior Notes [Member]	Aug. 31, 2009 Fixed Rate, 8.87% Series C Senior Notes [Member]	Sep. 30, 2009 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 9.125%, Due 2017 [Member]	Sep. 30, 2009 Fixed Rate, 9.125%, Due 2017 [Member]	Oct. 31, 2009 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 7.24% Series D Notes Due August 1, 2010 [Member]	Oct. 31, 2009 Fixed Rate, 7.24% Series D Notes Due August 1, 2010 [Member]	Oct. 31, 2009 Ferrellgas, L.P. And Subsidiaries [Member] Fixed Rate, 7.42% Series E Notes Due August 1, 2013 [Member]	Oct. 31, 2009 Fixed Rate, 7.42% Series E Notes Due August 1, 2013 [Member]	Apr. 30, 2010 Fixed Rate, 8.75% Senior Notes Due 2012 [Member]	Oct. 31, 2009 Ferrellgas, L.P. And Subsidiaries [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member]	Jul. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member]
Debt instrument, face amount								$ 500,000,000			$ 500,000,000	$ 450,000,000	$ 450,000,000	$ 280,000,000	$ 280,000,000	$ 280,000,000	$ 280,000,000			$ 300,000,000	$ 300,000,000
Debt instrument, interest rate						6.50%		6.50%	6.50%		6.50%	6.75%	6.75%	8.625%	8.625%	8.625%	8.625%	8.87%	8.87%	9.125%	9.125%	7.24%	7.24%	7.42%	7.42%	8.75%
Debt instrument, maturity year						2021		2021	2021		2021	2014	2014	2020	2020	2020	2020			2017	2017	2010	2010	2013	2013	2012
Proceeds from issuance of unsecured debt	273,400,000						491,300,000			491,300,000
Debt redeemed						500,000,000			500,000,000					98,000,000	98,000,000	98,000,000		73,000,000	73,000,000			82,000,000	82,000,000	70,000,000	70,000,000	268,000,000
Make-whole payment												11,100,000	11,100,000		8,400,000	8,400,000
Accrued interest paid												2,400,000	2,400,000		2,400,000	2,400,000
Unregistered notes, issuance date						November 24, 2010			November 24, 2010
Write-offs of unamortized discount on debt												25,300,000	25,300,000		2,200,000
Offering price as a percent of par value																				98.60%	98.60%
Prepayment premium for early extinguishment of debt		$ 17,300,000	$ (46,962,000)	$ (20,716,000)																						$ 3,400,000	$ 17,300,000	$ (36,449,000)	$ (17,308,000)