Consolidated Statements Of Partners' Capital (Deficit) - 3 months ended Oct. 31, 2017 - USD ($) $ in Thousands	Total	Accumulated Other Comprehensive Income (Loss)	Total Ferrellgas Partners, L.P. Partners' Capital (Deficit) [Member]	Noncontrolling Interest [Member]	Common Unitholders [Member]	General Partner Unitholder [Member]	Ferrellgas, L.P. [Member]	Ferrellgas, L.P. [Member] Accumulated Other Comprehensive Income (Loss)	Ferrellgas, L.P. [Member] Common Unitholders [Member]	Ferrellgas, L.P. [Member] General Partner Unitholder [Member]
Partners' capital balance (in units) at Jul. 31, 2017					97,152,700	989,900
Partners' capital balance at Jul. 31, 2017	$ (757,510)	$ 14,601	$ (753,578)	$ (3,932)	$ (701,188)	$ (66,991)	$ (406,798)	$ 14,764	$ (417,467)	$ (4,095)
Increase (Decrease) in Partners' Capital [Roll Forward]
Contributions in connection with non-cash ESOP and stock and unit-based compensation charges	3,962	0	3,923	39	3,883	40	3,962	0	3,923	39
Distributions	(9,913)	0	(9,813)	(100)	(9,715)	(98)	(9,913)	0	(9,813)	(100)
Net loss	(48,316)	0	(47,915)	(401)	$ (47,436)	$ (479)	(39,699)	0	(39,298)	(401)
Other comprehensive income (loss)	18,500	18,314	18,314	186			18,500	18,500	0	0
Partners' capital balance (in units) at Oct. 31, 2017					97,152,700	989,900
Partners' capital balance at Oct. 31, 2017	$ (793,277)	$ 32,915	$ (789,069)	$ (4,208)	$ (754,456)	$ (67,528)	$ (433,948)	$ 33,264	$ (462,655)	$ (4,557)