Partners' Deficit - Paid Distributions (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jan. 31, 2020	Oct. 31, 2019	Jan. 31, 2019	Oct. 31, 2018	Jan. 31, 2020	Jan. 31, 2019
Limited Partners' Capital Account [Line Items]
Distributions paid	$ 157	$ 1	$ 157	$ 9,915
Ferrellgas, L.P. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid	15,553	101	15,553	10,015	$ 15,654	$ 25,568
Ferrellgas Inc., General Partner [Member] | Ferrellgas, L.P. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid	157		157		158	258
Ferrellgas Partners LP [Member] | Ferrellgas, L.P. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid	15,396		15,396		$ 15,496	25,310
Parent [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid				9,814		9,814
Parent [Member] | Ferrell Companies [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						2,253
Parent [Member] | FCI Trading Corp. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						20
Parent [Member] | Ferrell Propane, Inc. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						5
Parent [Member] | James E. Ferrell [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						476
Parent [Member] | Ferrellgas Inc., General Partner [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						98
Common Unitholders [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid				9,716
Common Unitholders [Member] | Ferrellgas, L.P. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid	15,396	100	15,396	9,914
Public Common Unitholders [Member] | Parent [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid						$ 6,962
General Partner [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid				98
General Partner [Member] | Ferrellgas, L.P. [Member]
Limited Partners' Capital Account [Line Items]
Distributions paid	$ 157	$ 1	$ 157	$ 101