Supplemental Financial Statement Information - Shipping and Handling (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Supplemental Financial Statement Information [Line Items]
Operating expense - personnel, vehicle, plant and other	$ 128,233	$ 121,219	$ 242,776	$ 231,550
Depreciation and amortization expense	19,795	19,605	39,014	38,597
Operating expense - equipment lease expense	8,261		16,649
Equipment lease expense, preadoption		8,415		16,278
Ferrellgas, L.P. [Member]
Supplemental Financial Statement Information [Line Items]
Operating expense - personnel, vehicle, plant and other	128,233	121,219	242,776	231,550
Depreciation and amortization expense	19,795	19,605	39,014	38,597
Operating expense - equipment lease expense	8,261		16,649
Equipment lease expense, preadoption		8,415		16,278
Shipping and Handling [Member]
Supplemental Financial Statement Information [Line Items]
Operating expense - personnel, vehicle, plant and other	64,987	60,279	113,002	107,721
Depreciation and amortization expense	2,036	1,389	3,876	2,462
Operating expense - equipment lease expense	7,984		15,626
Equipment lease expense, preadoption		7,869		15,388
Costs and Expenses, Total	75,007	69,537	132,504	125,571
Shipping and Handling [Member] | Ferrellgas, L.P. [Member]
Supplemental Financial Statement Information [Line Items]
Operating expense - personnel, vehicle, plant and other	64,987	60,279	113,002	107,721
Depreciation and amortization expense	2,036	1,389	3,876	2,462
Operating expense - equipment lease expense	7,984		15,626
Equipment lease expense, preadoption		7,869		15,388
Costs and Expenses, Total	$ 75,007	$ 69,537	$ 132,504	$ 125,571