Contingencies And Commitments (Narrative) (Details)		6 Months Ended
Feb. 02, 2017 item	Jan. 31, 2019 USD ($) item
Loss Contingencies [Line Items]
Number of quarters for required fixed charge coverage ratio		4
Maximum restricted payments \| $		$ 50,000,000
Number of quarters for restricted payments		16
Current fixed charge coverage ratio		1.38
Dividends allowed \| $		$ 0
Minimum [Member]
Loss Contingencies [Line Items]
Required fixed charge coverage ratio		1.75
Class Action Related To Cylinder Fill Level [Member]
Loss Contingencies [Line Items]
Number of cases		1
Lawsuit Related To Sale Of Jamex Transfer Services [Member]
Loss Contingencies [Line Items]
Number of former officers	2
Ferrellgas Partners Finance Corp. [Member]
Loss Contingencies [Line Items]
Number of quarters for required fixed charge coverage ratio		4
Maximum restricted payments \| $		$ 50,000,000
Number of quarters for restricted payments		16
Current fixed charge coverage ratio		1.67
Dividends allowed \| $		$ 0
Ferrellgas Partners Finance Corp. [Member] \| Minimum [Member]
Loss Contingencies [Line Items]
Required fixed charge coverage ratio		1.75
Ferrellgas, L.P. [Member]
Loss Contingencies [Line Items]
Number of quarters for required fixed charge coverage ratio		4
Current fixed charge coverage ratio		1.67
Ferrellgas, L.P. [Member] \| Minimum [Member]
Loss Contingencies [Line Items]
Required fixed charge coverage ratio		1.75
Ferrellgas, L.P. [Member] \| Class Action Related To Cylinder Fill Level [Member]
Loss Contingencies [Line Items]
Number of cases		1
Ferrellgas, L.P. [Member] \| Lawsuit Related To Sale Of Jamex Transfer Services [Member]
Loss Contingencies [Line Items]
Number of former officers	2

The amount of dividends that may be paid, under the debt securities covenant, while the entity is in default.

No definition available.

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Namespace Prefix:	fgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The current ratio of trailing four quarters EBITDA to interest expense, under the indenture governing the debt securities. Compliance status entitles, or prevents, the entity from taking certain actions.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of restricted payments the entity may make under certain conditions, per the indenture governing debt securities.

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of quarters during which the restricted payment may be made.

+ References

No definition available.

+ Details

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

- Definition

The required ratio of trailing four quarters EBITDA to interest expense, under the indenture governing the debt securities. Compliance status entitles, or prevents, the entity from taking certain actions.

+ References

No definition available.

+ Details

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

- Definition

The number of quarters EBITDA used in the required fixed charge coverage ratio.

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
Data Type:	xbrli:integerItemType
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Number of defendants named in a legal action.

+ References

No definition available.

+ Details

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

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

+ Details

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

- Details

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- Details

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- Details

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- Details

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- Details

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