Supplemental Financial Statement Information (Shipping And Handling Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	$ 56,198	$ 51,830	$ 168,726	$ 156,951
Ferrellgas, L.P. [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	56,198	51,830	168,726	156,951
Operating Expense [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	48,351	44,309	146,279	134,090
Operating Expense [Member] | Ferrellgas, L.P. [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	48,351	44,309	146,279	134,090
Depreciation And Amortization Expense [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	1,340	957	3,575	2,979
Depreciation And Amortization Expense [Member] | Ferrellgas, L.P. [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	1,340	957	3,575	2,979
Equipment Lease Expense [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	6,507	6,564	18,872	19,882
Equipment Lease Expense [Member] | Ferrellgas, L.P. [Member]
Condensed Financial Statements, Captions [Line Items]
Shipping and handling expenses	$ 6,507	$ 6,564	$ 18,872	$ 19,882