Supplemental Financial Statement Information (Narrative) (Details) $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 20, 2018 USD ($)	Jan. 31, 2018 USD ($) gal	Jan. 31, 2017 USD ($)	Jan. 31, 2018 USD ($) gal	Jan. 31, 2017 USD ($)
Number of rail cars held for sale		1,292		1,292
Impairment of Long-Lived Assets to be Disposed of		$ 35,515	$ 0	$ 35,515	$ 0
Number of rail cars sold	1,072
Loss on sale of assets and other		$ 3,734	45	$ 4,629	6,468
Proceeds from Sale of Property, Plant, and Equipment	$ 47,000
Maximum term of supply procurement contracts				36 months
Net procurement of fixed priced propane in gallons | gal		81,900,000		81,900,000
Other Assets, Noncurrent		$ 8,500		$ 8,500
Ferrellgas, L.P. [Member]
Number of rail cars held for sale		1,292		1,292
Impairment of Long-Lived Assets to be Disposed of		$ 35,515	0	$ 35,515	0
Number of rail cars sold	1,072
Loss on sale of assets and other		$ 3,734	$ 45	$ 4,629	$ 6,468
Proceeds from Sale of Property, Plant, and Equipment	$ 47,000
Maximum term of supply procurement contracts				36 months
Net procurement of fixed priced propane in gallons | gal		81,900,000		81,900,000
Other Assets, Noncurrent		$ 8,500		$ 8,500
Loss on asset sale [Member]
Loss on sale of assets and other				3,600
Loss on asset sale [Member] | Ferrellgas, L.P. [Member]
Loss on sale of assets and other				$ 3,600