Debt (Senior Notes Narrative) (Details) (USD $)	12 Months Ended
Jul. 31, 2013
Fixed Rate, 6.50%, Due 2021 [Member]
Senior note, issuance date	Nov. 24, 2010
Debt instrument, face amount	$ 500,000,000.0
Interest rate	6.50%
Proceeds from issuance of unsecured debt	491,300,000
Debt Instrument, Frequency of Periodic Payment	semi-annually
Debt instrument, maturity date	May 01, 2021
Debt instrument prepayment penalty prior to date	2019
Debt Conversion, Converted Instrument, Issuance Date	Jul. 07, 2011
Debt Conversion, Converted Instrument, Amount	500,000,000.0
Debt Conversion, Converted Instrument, Rate	6.50%
Debt Conversion, Converted Instrument, Expiration or Due Date, Year	2021
Debt Conversion, Converted Instrument, Type	registered
Debt Conversion, Original Debt, Type of Debt	unregistered
Fixed Rate, 6.50%, Due 2021 [Member] \| Ferrellgas, L.P. [Member]
Senior note, issuance date	Nov. 24, 2010
Debt instrument, face amount	500,000,000.0
Interest rate	6.50%
Proceeds from issuance of unsecured debt	491,300,000
Debt Instrument, Frequency of Periodic Payment	semi-annually
Debt instrument, maturity date	May 01, 2021
Debt instrument prepayment penalty prior to date	2019
Debt Conversion, Converted Instrument, Issuance Date	Jul. 07, 2011
Debt Conversion, Converted Instrument, Amount	500,000,000.0
Debt Conversion, Converted Instrument, Rate	6.50%
Debt Conversion, Converted Instrument, Expiration or Due Date, Year	2021
Debt Conversion, Converted Instrument, Type	registered
Debt Conversion, Original Debt, Type of Debt	unregistered
Fixed Rate, 6.75%, Due 2014 [Member]
Interest rate	6.75%
Debt instrument, maturity year	2014
Debt redeemed	450,000,000.0
Make-whole payment	11,100,000
Accrued interest paid	2,400,000
Write-offs of unamortized discount on debt	25,300,000
Fixed Rate, 6.75%, Due 2014 [Member] \| Ferrellgas, L.P. [Member]
Interest rate	6.75%
Debt instrument, maturity year	2014
Debt redeemed	450,000,000.0
Make-whole payment	11,100,000
Accrued interest paid	2,400,000
Write-offs of unamortized discount on debt	25,300,000
Fixed Rate, 9.125%, Due 2017 [Member]
Senior note, issuance date	Sep. 14, 2009
Debt instrument, face amount	300,000,000.0
Debt Instrument, Frequency of Periodic Payment	semi-annually
Debt instrument, maturity date	Oct. 01, 2017
Debt Instrument, Unamortized Discount	4,200,000
Debt instrument prepayment penalty prior to date	2015
Fixed Rate, 9.125%, Due 2017 [Member] \| Ferrellgas, L.P. [Member]
Senior note, issuance date	Sep. 14, 2009
Debt instrument, face amount	300,000,000.0
Debt Instrument, Frequency of Periodic Payment	semi-annually
Debt instrument, maturity date	Oct. 01, 2017
Debt Instrument, Unamortized Discount	4,200,000
Debt instrument prepayment penalty prior to date	2015
Fixed Rate, 8.625%, Due 2020 [Member]
Senior note, issuance date	Apr. 13, 2010
Debt instrument, face amount	280,000,000.0
Debt redeemed	98,000,000
Make-whole payment	8,400,000
Accrued interest paid	2,400,000
Debt Instrument, Frequency of Periodic Payment	semi-annually
Debt instrument prepayment penalty prior to date	2018
Write-offs of unamortized discount on debt	$ 2,200,000

Accrued interest paid on senior notes.

No definition available.

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Namespace Prefix:	fgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument, make whole payment

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Prepayment penalties will be incurred if debt is paid off prior to this date.

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, principal amount redeemed

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt maturity year

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	instant

- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Year of expiration or mandatory redemption of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction, in CCYY format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the financial instrument was issued in exchange for the original debt being converted in a noncash or part noncash transaction, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The type of the financial instrument that the original debt is being converted into (for example, new debt, common stock, preferred stock, etc.) in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

A textual description providing detail about the type of debt (for example, secured, unsecured, callable, convertible) that is being converted in a noncash (or part noncash) transaction. At a minimum, the disclosure includes information sufficient to provide an understanding of the nature and purpose of the debt issuance, as well as its features and the events leading to up to conversion. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments during the period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: 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 2: 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ 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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: 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=31042434&loc=d3e3255-108585

+ Details

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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 Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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