Derivative Instruments and Hedging Activities (Fair Value of Financial Derivatives Balance Sheet Locations) (Details) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2015	Jul. 31, 2014
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	$ 5,083	$ 7,006
Interest rate swap assets	2,145	2,101
Derivative assets, fair value	7,228	9,107
Propane commodity derivative liabilities	27,236	83
Interest rate swap liabilities	3,689	5,075
Derivative liabilities, fair value	30,925	5,158
Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	5,083	7,006
Interest rate swap assets	2,145	2,101
Derivative assets, fair value	7,228	9,107
Propane commodity derivative liabilities	27,236	83
Interest rate swap liabilities	3,689	5,075
Derivative liabilities, fair value	30,925	5,158
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	1,550	5,301
Interest rate swap assets	1,950	2,101
Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net	734
Prepaid Expenses and Other Current Assets [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	1,550	5,301
Interest rate swap assets	1,950	2,101
Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net	734
Other assets, net [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	1,893	1,705
Interest rate swap assets	195	0
Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net	906
Other assets, net [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative assets	1,893	1,705
Interest rate swap assets	195	0
Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net	906
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative liabilities	20,709	83
Interest rate swap liabilities	1,660	0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	0
Other Current Liabilities [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative liabilities	20,709	83
Interest rate swap liabilities	1,660	0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	0
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative liabilities	6,527	0
Interest rate swap liabilities	2,029	5,075
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	0
Other Liabilities [Member] \| Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Propane commodity derivative liabilities	6,527	0
Interest rate swap liabilities	2,029	5,075
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	$ 0

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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Fair value, before effects of master netting arrangements, of a financial liability or 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 liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Fair value as of the balance sheet date of price risk derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets on the balance sheet.

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Fair value as of the balance sheet date of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities on the balance sheet.

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