Quarterly Distributions Of Available Cash (Details)	12 Months Ended
	Jul. 31, 2020 item
Earnings Distribution Allocation [Line Items]
Cash reserve for distributions, number of quarters provided	4
Maximum days after end of quarter to make distributions	45 days
Cash distributions available	100.00%
Ferrellgas, L.P. [Member]
Earnings Distribution Allocation [Line Items]
Cash reserve for distributions, number of quarters provided	4
Maximum days after end of quarter to make distributions	45 days
Cash distributions available	100.00%
Cash distributions to Ferrellgas Partners	99.00%
Cash distributions to general partner	1.00%