Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Deferred tax expense (benefit)	$ 11,000	$ (504,000)	$ 270,000
Deferred tax assets	1,068,000	1,156,000
Ferrellgas Partners Finance Corp. [Member]
Deferred tax assets, operating loss carryforwards	9,532
Net operating loss carryforward	$ 24,505
Net operating loss carryforward, expiration date	Jul. 31, 2037
Deferred tax expense (benefit)	$ 0	0	0
Deferred tax assets	0	0
Valuation allowance provided for deferred tax asset	6,588
Ferrellgas Finance Corp. [Member]
Deferred tax assets, operating loss carryforwards	25,591
Net operating loss carryforward	$ 65,787
Net operating loss carryforward, expiration date	Jul. 31, 2037
Deferred tax expense (benefit)	$ 0	0	$ 0
Deferred tax assets	0	$ 0
Valuation allowance provided for deferred tax asset	$ 20,701