Derivative Instruments and Hedging Activities (Cash Flow Derivative Value Recorded in OCI and reclassified to Earnings) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Amount of gain (loss) recognized in AOCI(L) on derivative	$ (6,205)	$ (1,347)	$ 71	$ (3,875)
Amount of gain (loss) reclassified from AOCI(L)	(4,434)	834	(8,625)	2,713
Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(6,205)	(1,347)	71	(3,875)
Amount of gain (loss) reclassified from AOCI(L)	(4,434)	834	(8,625)	2,713
Commodity Derivatives Propane [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(5,612)	(1,347)	914	(3,875)
Reclassification of gains (losses) from AOCI(L) to Cost of product sold - propane and other gas liquids	(4,434)	834	(8,625)	2,713
Commodity Derivatives Propane [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(5,612)	(1,347)	914	(3,875)
Reclassification of gains (losses) from AOCI(L) to Cost of product sold - propane and other gas liquids	(4,434)	834	(8,625)	2,713
Interest Rate Swap [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	(593)		(843)
Interest Rate Swap [Member] | Ferrellgas, L.P. [Member]
Amount of gain (loss) recognized in AOCI(L) on derivative	$ (593)		$ (843)