Transactions With Related Parties (Schedule Of Transactions With Related Parties) (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2017	Oct. 31, 2016
Related Party Transaction [Line Items]
General and administrative expense	$ 13,164	$ 14,269
Ferrellgas, L.P. [Member]
Related Party Transaction [Line Items]
General and administrative expense	13,164	14,269
Compensation And Benefits [Member]
Related Party Transaction [Line Items]
Operating expense	57,351	55,714
General and administrative expense	7,508	8,583
Compensation And Benefits [Member] | Ferrellgas, L.P. [Member]
Related Party Transaction [Line Items]
Operating expense	57,351	55,714
General and administrative expense	$ 7,508	$ 8,583