Derivative Instruments and Hedging Activities - Balance Sheet (Details) - USD ($)	24 Months Ended
Jul. 31, 2019	Jul. 31, 2018	May 03, 2018
Derivatives, Fair Value [Line Items]
Gain (loss) recognized due to ineffectiveness	$ 0
Commodity derivatives propane swap assets	1,259,000	$ 22,470,000
Derivative Asset, Fair Value, Gross Asset	1,259,000	22,470,000	$ 4,200,000
Commodity derivatives propane swap liabilities	16,015,000	1,910,000
Derivative Liability, Fair Value, Gross Liability	16,015,000	1,910,000
Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) recognized due to ineffectiveness	0
Commodity derivatives propane swap assets	1,259,000	22,470,000
Derivative Asset, Fair Value, Gross Asset	1,259,000	22,470,000	$ 4,200,000
Commodity derivatives propane swap liabilities	16,015,000	1,910,000
Derivative Liability, Fair Value, Gross Liability	16,015,000	1,910,000
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	910,000	17,123,000
Prepaid Expenses and Other Current Assets [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	910,000	17,123,000
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	14,198,000	1,832,000
Other Current Liabilities [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	14,198,000	1,832,000
Other Assets, Net [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	349,000	5,347,000
Other Assets, Net [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap assets	349,000	5,347,000
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	1,817,000	78,000
Other Liabilities [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Commodity derivatives propane swap liabilities	$ 1,817,000	$ 78,000

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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