Segment Reporting Segment Reporting (Reconciliation of Assets from Segment to Consolidated) (Details) - USD ($) $ in Thousands	Oct. 31, 2017	Jul. 31, 2017
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 1,704,954	$ 1,609,969
Propane and related equipment sales [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	1,292,686	1,194,905
Midstream - Crude Oil Logistics [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	397,653	399,356
Corporate and Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	14,615	15,708
Ferrellgas, L.P. [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	1,704,939	1,609,948
Ferrellgas, L.P. [Member] | Propane and related equipment sales [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	1,292,686	1,194,905
Ferrellgas, L.P. [Member] | Midstream - Crude Oil Logistics [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	397,653	399,356
Ferrellgas, L.P. [Member] | Corporate and Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 14,600	$ 15,687