Guarantor financial information (Details) - Ferrellgas, L.P. [Member] $ in Millions	Jan. 31, 2019 USD ($)
Ferrellgas Finance Corp. [Member]
Condensed Financial Statements, Captions [Line Items]
Ownership Percentage	100.00%
Fixed Rate Six Point Seven Five Due Two Thousand Twenty Three [Member]
Condensed Financial Statements, Captions [Line Items]
Aggregate principal amount	$ 500.0
Interest rate, as a percent	6.75%

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.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Paragraph 8
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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