Derivative Instruments and Hedging Activities - Derivative Collateral (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jul. 31, 2020
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	$ 20,857	$ 15,831
Derivative Liability, Fair Value of Collateral	41,869	510
Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	19,410	14,398
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	39,774	510
Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	1,447	1,433
Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	2,095
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	20,857	15,831
Derivative Liability, Fair Value of Collateral	41,869	510
Ferrellgas, L.P. [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	19,410	14,398
Ferrellgas, L.P. [Member] \| Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	39,774	510
Ferrellgas, L.P. [Member] \| Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	1,447	$ 1,433
Ferrellgas, L.P. [Member] \| Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	$ 2,095

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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