Derivative Instruments and Hedging Activities (Fair Value Hedge Derivative Effect on Earnings) (Details) (Interest Rate Swap [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Gain (loss) recognized on derivative	$ 587	$ 489	$ 1,043	$ 1,321
Interest expense recognized on fixed-rate debt	(2,275)	(2,275)	(4,550)	(7,640)
Ferrellgas, L.P. [Member]
Gain (loss) recognized on derivative	587	489	1,043	1,321
Interest expense recognized on fixed-rate debt	$ (2,275)	$ (2,275)	$ (4,550)	$ (7,640)