Derivative Instruments and Hedging Activities (Cash Flow Hedge Derivative Effect on Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Derivative [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	$ 14,592	$ 4,252
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)
Derivative [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	14,592	4,252
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)
Commodity Derivatives Propane [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	15,473	2,032	(23,290)
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)	(7,108)
Commodity Derivatives Propane [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	15,473	2,032	(23,290)
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)	(7,108)
Interest Rate Swap [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(881)	2,220	(1,778)
Interest Rate Swap [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(881)	2,220	(1,778)
Cost of Sales [Member] | Commodity Derivatives Propane [Member]
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)
Cost of Sales [Member] | Commodity Derivatives Propane [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) reclassified from AOCI into income	10,175	(10,613)
Interest Expense [Member] | Interest Rate Swap [Member]
Amount of gain (loss) reclassified from AOCI into income	0	0
Interest Expense [Member] | Interest Rate Swap [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) reclassified from AOCI into income	$ 0	$ 0