Derivative Instruments and Hedging Activities - Derivative Collateral (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jul. 31, 2018
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	$ 27,997	$ 3,778
Derivative Liability, Fair Value of Collateral	1,217	16,543
Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	25,028	2,851
Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	1,217	12,308
Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	2,969	927
Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral		4,235
Ferrellgas, L.P. [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	27,997	3,778
Derivative Liability, Fair Value of Collateral	1,217	16,543
Ferrellgas, L.P. [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	25,028	2,851
Ferrellgas, L.P. [Member] \| Other Current Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral	1,217	12,308
Ferrellgas, L.P. [Member] \| Other Assets, Net [Member]
Derivative [Line Items]
Derivative Asset, Fair Value of Collateral	$ 2,969	927
Ferrellgas, L.P. [Member] \| Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value of Collateral		$ 4,235

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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