Supplemental Information - Prepaids and Other Assets (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jul. 31, 2020
Supplemental Financial Statement Information [Line Items]
Broker margin deposit assets	$ 19,410	$ 14,398
Price risk management asset	32,270	2,846
Other assets, net	21,234	18,700
Prepaid expenses and other current assets	72,914	35,944
Finance lease right-of-use assets	38,045	41,426
Other assets, net	91,159	74,748
Ferrellgas, L.P. [Member]
Supplemental Financial Statement Information [Line Items]
Broker margin deposit assets	19,410	14,398
Price risk management asset	32,270	2,846
Other assets, net	21,426	18,653
Prepaid expenses and other current assets	73,106	35,897
Finance lease right-of-use assets	38,045	41,426
Other assets, net	$ 91,159	$ 74,748