Derivative Instruments and Hedging Activities - Derivative Collateral (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jul. 31, 2019
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	$ 34,949	$ 27,997
Derivative Liability, Fair Value of Collateral	4,344	1,217
Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	33,436	25,028
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	4,236	1,217
Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	1,513	2,969
Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	108
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	34,949	27,997
Derivative Liability, Fair Value of Collateral	4,344	1,217
Ferrellgas, L.P. [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	33,436	25,028
Ferrellgas, L.P. [Member] \| Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	4,236	1,217
Ferrellgas, L.P. [Member] \| Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	1,513	$ 2,969
Ferrellgas, L.P. [Member] \| Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	$ 108

Fair value of securities received as collateral against derivative assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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Fair value of securities pledged as collateral against derivative liabilities.

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