Derivative Instruments and Hedging Activities (Cash Flow Hedge Derivative Effect on Comprehensive Income) (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
Amount of gain (loss) recognized in AOCI	$ 7,919	$ 660	$ (51,105)	$ 17,047
Amount of gain (loss) reclassified from AOCI into income	(10,907)	(3,885)	(17,139)	8,640
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	(199)	0
Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI	7,919	660	(51,105)	17,047
Amount of gain (loss) reclassified from AOCI into income	(10,907)	(3,885)	(17,139)	8,640
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	(199)	0
Propane commodity derivatives [Member]
Amount of gain (loss) recognized in AOCI	7,813	(165)	(47,855)	17,298
Amount of gain (loss) reclassified from AOCI into income			(17,139)	8,640
Propane commodity derivatives [Member] \| Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI	7,813	(165)	(47,855)	17,298
Amount of gain (loss) reclassified from AOCI into income			(17,139)	8,640
Interest Rate Swap [Member]
Amount of gain (loss) recognized in AOCI	106	825	(3,250)	(251)
Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI	106	825	(3,250)	(251)
Cost of Product Sold [Member] \| Propane commodity derivatives [Member]
Amount of gain (loss) reclassified from AOCI into income	(10,907)	(3,885)	(17,139)	8,640
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	0	0
Cost of Product Sold [Member] \| Propane commodity derivatives [Member] \| Ferrellgas, L.P. [Member]
Amount of gain (loss) reclassified from AOCI into income	(10,907)	(3,885)	(17,139)	8,640
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	0	0
Interest Expense [Member] \| Propane commodity derivatives [Member] \| Ferrellgas, L.P. [Member]
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	(199)	0
Interest Expense [Member] \| Interest Rate Swap [Member]
Amount of gain (loss) reclassified from AOCI into income	0	0	0	0
Amount of gain (loss) reclassified from AOCI into income, ineffective portion	0	0	(199)	0
Interest Expense [Member] \| Interest Rate Swap [Member] \| Ferrellgas, L.P. [Member]
Amount of gain (loss) reclassified from AOCI into income	$ 0	$ 0	$ 0	$ 0

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1),(2)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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