Income Taxes (Details) - USD ($)	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Income Tax Disclosure [Line Items]
Deferred income tax expense (benefit)	$ 554,000	$ 143,000	$ (3,818,000)
Deferred tax assets	4,000	631,000
Ferrellgas Partners Finance Corp. [Member]
Income Tax Disclosure [Line Items]
Deferred tax assets, operating loss carryforwards		7,606
Net operating loss carryforward		36,221
Valuation allowance provided for deferred tax asset	7,606
Deferred income tax expense (benefit)	0	0	0
Deferred tax assets	0	0	0
Ferrellgas Finance Corp. [Member]
Income Tax Disclosure [Line Items]
Deferred tax assets, operating loss carryforwards		17,426
Net operating loss carryforward		82,979
Valuation allowance provided for deferred tax asset	17,426
Deferred income tax expense (benefit)	0	0	$ 0
Deferred tax assets	$ 0	$ 0