Segment Reporting Segment Reporting (Schedule of Capital Expenditure Information, by Segment) (Details) - USD ($) $ in Thousands	9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017
Segment Reporting Information
Capital Expenditures	$ 55,307	$ 31,925
Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	52,340	29,779
Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	1,492	1,905
Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	1,475	241
Maintenance Capital Expenditures [Member]
Segment Reporting Information
Capital Expenditures	19,258	10,679
Maintenance Capital Expenditures [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	17,556	8,533
Maintenance Capital Expenditures [Member] | Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	1,492	1,905
Maintenance Capital Expenditures [Member] | Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	210	241
Growth Capital Expenditures [Member]
Segment Reporting Information
Capital Expenditures	36,049	21,246
Growth Capital Expenditures [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	34,784	21,246
Growth Capital Expenditures [Member] | Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	0	0
Growth Capital Expenditures [Member] | Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	1,265	0
Ferrellgas, L.P. [Member]
Segment Reporting Information
Capital Expenditures	55,307	31,925
Ferrellgas, L.P. [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	52,340	29,779
Ferrellgas, L.P. [Member] | Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	1,492	1,905
Ferrellgas, L.P. [Member] | Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	1,475	241
Ferrellgas, L.P. [Member] | Maintenance Capital Expenditures [Member]
Segment Reporting Information
Capital Expenditures	19,258	10,679
Ferrellgas, L.P. [Member] | Maintenance Capital Expenditures [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	17,556	8,533
Ferrellgas, L.P. [Member] | Maintenance Capital Expenditures [Member] | Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	1,492	1,905
Ferrellgas, L.P. [Member] | Maintenance Capital Expenditures [Member] | Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	210	241
Ferrellgas, L.P. [Member] | Growth Capital Expenditures [Member]
Segment Reporting Information
Capital Expenditures	36,049	21,246
Ferrellgas, L.P. [Member] | Growth Capital Expenditures [Member] | Propane and related equipment sales [Member]
Segment Reporting Information
Capital Expenditures	34,784	21,246
Ferrellgas, L.P. [Member] | Growth Capital Expenditures [Member] | Corporate Segment [Member]
Segment Reporting Information
Capital Expenditures	0	0
Ferrellgas, L.P. [Member] | Growth Capital Expenditures [Member] | Midstream Operations [Member]
Segment Reporting Information
Capital Expenditures	$ 1,265	$ 0