Debt Debt (Maximum Leverage Ratio Schedule) (Details) - Maximum [Member]	3 Months Ended
Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018
Debt Instrument [Line Items]
required total leverage ratio	550.00%	775.00%	775.00%
Ferrellgas, L.P. [Member]
Debt Instrument [Line Items]
required total leverage ratio	550.00%	775.00%	775.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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