Leases - Cash Flow (Details) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Operating cash flows, operating leases	$ 17,546	$ 21,647
Operating cash flows, financing leases	1,729	360
Financing cash flows, financing leases	3,460	320
Ferrellgas, L.P. [Member]
Operating cash flows, operating leases	17,546	21,647
Operating cash flows, financing leases	1,729	360
Financing cash flows, financing leases	$ 3,460	$ 320