Derivative Instruments and Hedging Activities (Changes in Derivative Value Effect on Other Comprehensive Income Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014	Jul. 31, 2014	Jul. 31, 2013
Beginning balance	$ (27,247)		$ (27,247)		$ 6,181
Change in value of risk management derivatives	7,919	660	(51,105)	17,047
Reclassification of gains and losses on commodity hedges to cost of product sold - propane and other gas liquids sales	10,907	3,885	17,139	(8,640)
Ending balance	(27,247)		(27,247)		6,181
Ferrellgas, L.P. [Member]
Beginning balance	(27,511)		(27,511)		6,258
Change in value of risk management derivatives	7,919	660	(51,105)	17,047
Reclassification of gains and losses on commodity hedges to cost of product sold - propane and other gas liquids sales	10,907	3,885	17,139	(8,640)
Ending balance	(27,511)		(27,511)		6,258
Propane commodity derivatives [Member]
Change in value of risk management derivatives	7,813	(165)	(47,855)	17,298
Reclassification of gains and losses on commodity hedges to cost of product sold - propane and other gas liquids sales			17,139	(8,640)
Propane commodity derivatives [Member] \| Ferrellgas, L.P. [Member]
Change in value of risk management derivatives	7,813	(165)	(47,855)	17,298
Reclassification of gains and losses on commodity hedges to cost of product sold - propane and other gas liquids sales			17,139	(8,640)
Interest Rate Swap [Member]
Change in value of risk management derivatives	106	825	(3,250)	(251)
Derivative, Net Hedge Ineffectiveness Gain (Loss)			199	0
Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member]
Change in value of risk management derivatives	106	825	(3,250)	(251)
Derivative, Net Hedge Ineffectiveness Gain (Loss)			199	0
Derivative [Member]
Beginning balance	(27,284)	10,473	(27,284)	10,473	6,483	2,066
Ending balance	(27,284)	10,473	(27,284)	10,473	6,483	2,066
Derivative [Member] \| Ferrellgas, L.P. [Member]
Beginning balance	(27,284)	10,473	(27,284)	10,473	6,483	2,066
Ending balance	$ (27,284)	$ 10,473	$ (27,284)	$ 10,473	$ 6,483	$ 2,066

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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