Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities (Schedule of Derivative Collateral) (Details) - USD ($) $ in Thousands	Oct. 31, 2016	Jul. 31, 2016
Derivative Asset, Fair Value of Collateral	$ 4,585	$ 9,527
Derivative Liability, Fair Value of Collateral	3,443	0
Ferrellgas, L.P. [Member]
Derivative Asset, Fair Value of Collateral	4,585	9,527
Derivative Liability, Fair Value of Collateral	3,443	0
Other assets, net [Member]
Derivative Asset, Fair Value of Collateral	1,287	1,275
Other assets, net [Member] | Ferrellgas, L.P. [Member]
Derivative Asset, Fair Value of Collateral	1,287	1,275
Prepaid Expenses and Other Current Assets [Member]
Derivative Asset, Fair Value of Collateral	3,298	8,252
Prepaid Expenses and Other Current Assets [Member] | Ferrellgas, L.P. [Member]
Derivative Asset, Fair Value of Collateral	3,298	8,252
Other Current Liabilities [Member]
Derivative Liability, Fair Value of Collateral	747	0
Other Current Liabilities [Member] | Ferrellgas, L.P. [Member]
Derivative Liability, Fair Value of Collateral	747	0
Other Liabilities [Member]
Derivative Liability, Fair Value of Collateral	2,696	0
Other Liabilities [Member] | Ferrellgas, L.P. [Member]
Derivative Liability, Fair Value of Collateral	$ 2,696	$ 0