Debt - Covenants (Details) $ in Millions		3 Months Ended
Nov. 07, 2019	Oct. 31, 2019 USD ($) item
Debt Instrument [Line Items]
Required fixed charge coverage ratio		175.00%
Lease commitment reimbursement period	9 months
Ferrellgas Partners LP [Member]
Debt Instrument [Line Items]
Number of quarters for required fixed charge coverage ratio		4
Required fixed charge coverage ratio		175.00%
Maximum restricted payments \| $		$ 50.0
Number of quarters for restricted payments		16
Current fixed charge coverage ratio		135.00%
Dividends allowed \| $		$ 0.0
Ferrellgas Partners LP [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Current fixed charge coverage ratio		175.00%
Ferrellgas, L.P. [Member]
Debt Instrument [Line Items]
Number of quarters for required fixed charge coverage ratio		4
Required fixed charge coverage ratio		175.00%
Current fixed charge coverage ratio		168.00%
Lease commitment reimbursement period	9 months
Ferrellgas, L.P. [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Current fixed charge coverage ratio		175.00%

The period in which lease commitments are to be reimbursed in accordance with debt covenants.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	fgp_
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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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Period Type:	duration

- 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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- 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_
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Balance Type:	na
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- Definition

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

+ References

No definition available.

+ Details

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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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- Details

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- Details

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- Details

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