Transactions With Related Parties (Details) $ in Thousands	3 Months Ended
	Oct. 31, 2020 USD ($) employee	Oct. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Entity Number of Employees | employee	0
Ferrellgas Inc., General Partner [Member] | Operating Expense [Member]
Related Party Transaction [Line Items]
Expenses reimbursed to related party | $	$ 60,980	$ 63,471
Ferrellgas Inc., General Partner [Member] | General and Administrative Expense [Member]
Related Party Transaction [Line Items]
Expenses reimbursed to related party | $	$ 6,719	6,487
Ferrellgas, L.P. [Member]
Related Party Transaction [Line Items]
Entity Number of Employees | employee	0
Ferrellgas, L.P. [Member] | Ferrellgas Inc., General Partner [Member] | Operating Expense [Member]
Related Party Transaction [Line Items]
Expenses reimbursed to related party | $	$ 60,980	63,471
Ferrellgas, L.P. [Member] | Ferrellgas Inc., General Partner [Member] | General and Administrative Expense [Member]
Related Party Transaction [Line Items]
Expenses reimbursed to related party | $	$ 6,719	$ 6,487
Ferrellgas Finance Corp. [Member]
Related Party Transaction [Line Items]
Entity Number of Employees | employee	0
Ferrellgas Partners Finance Corp. [Member]
Related Party Transaction [Line Items]
Entity Number of Employees | employee	0