Derivative Instruments and Hedging Activities - Margin Balances (Details) - USD ($) $ in Thousands	Apr. 30, 2022	Jul. 31, 2021
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	$ 17,394	$ 24,104
Derivative Liability, Fair Value of Collateral	78,470	94,667
Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	11,938	21,068
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	67,200	79,178
Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	5,456	3,036
Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	11,270	15,489
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	17,394	24,104
Derivative Liability, Fair Value of Collateral	78,470	94,667
Ferrellgas, L.P. [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	11,938	21,068
Ferrellgas, L.P. [Member] \| Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	67,200	79,178
Ferrellgas, L.P. [Member] \| Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	5,456	3,036
Ferrellgas, L.P. [Member] \| Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	$ 11,270	$ 15,489

Fair value of securities received as collateral against derivative assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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