Schedule I Parent Only Statements - Operations (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Condensed Income Statements, Captions [Line Items]
General and administrative expense													$ 59,994	$ 54,401	$ 49,617
Operating income (loss)													113,028	(91,964)	95,367
Interest expense													(177,619)	(168,467)	(152,485)
Other income, net													369	928	1,474
Income tax expense (benefit)													323	(2,678)	(1,143)
Net loss	$ (71,672)	$ 20,760	$ 43,875	$ (57,508)	$ (217,797)	$ 11,062	$ (1,774)	$ (48,316)	$ (56,249)	$ 6,691	$ 38,528	$ (43,471)	(64,545)	(256,825)	(54,501)
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Equity in earnings (loss) of Ferrellgas, L.P.													(29,219)	(219,902)	(28,765)
General and administrative expense													14	137	139
Operating income (loss)													(29,233)	(220,039)	(28,904)
Interest expense													(34,984)	(34,521)	(25,297)
Income tax expense (benefit)													30	21	6
Net loss													$ (64,247)	$ (254,581)	$ (54,207)