Segment Reporting Segment Reporting (Schedule of Segment Reporting Information, by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017
Segment Reporting Information
Revenues	$ 515,810	$ 538,109	$ 1,725,621	$ 1,496,901
Costs and Expenses	428,888	461,319	1,491,856	1,286,062
Adjusted EBITDA	86,922	76,790	233,765	210,839
Propane and related equipment sales [Member]
Segment Reporting Information
Revenues	493,215	411,433	1,464,990	1,165,394
Costs and Expenses	397,568	324,442	1,208,283	931,631
Adjusted EBITDA	95,647	86,991	256,707	233,763
Midstream Operations [Member]
Segment Reporting Information
Revenues	22,595	126,676	260,631	331,507
Costs and Expenses	21,593	127,223	250,423	323,714
Adjusted EBITDA	1,002	(547)	10,208	7,793
Corporate Segment [Member]
Segment Reporting Information
Revenues	0	0	0	0
Costs and Expenses	9,727	9,654	33,150	30,717
Adjusted EBITDA	(9,727)	(9,654)	(33,150)	(30,717)
Ferrellgas, L.P. [Member]
Segment Reporting Information
Revenues	515,810	538,109	1,725,621	1,496,901
Costs and Expenses	428,756	461,210	1,491,723	1,285,952
Adjusted EBITDA	87,054	76,899	233,898	210,949
Ferrellgas, L.P. [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Revenues	493,215	411,433	1,464,990	1,165,394
Costs and Expenses	397,568	324,442	1,208,283	931,631
Adjusted EBITDA	95,647	86,991	256,707	233,763
Ferrellgas, L.P. [Member] | Midstream Operations [Member]
Segment Reporting Information
Revenues	22,595	126,676	260,631	331,507
Costs and Expenses	21,593	127,223	250,423	323,714
Adjusted EBITDA	1,002	(547)	10,208	7,793
Ferrellgas, L.P. [Member] | Corporate Segment [Member]
Segment Reporting Information
Revenues	0	0	0	0
Costs and Expenses	9,595	9,545	33,017	30,607
Adjusted EBITDA	$ (9,595)	$ (9,545)	$ (33,017)	$ (30,607)