Supplemental Financial Statement Information - Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2019	Jan. 31, 2018
Supplemental Financial Statement Information [Line Items]
Interest Paid	$ 82,941	$ 78,682
Income Taxes Paid	2	12
Noncash Investing and Financing Items [Abstract]
Liabilities incurred in connection with acquisitions	1,174	1,508
Change in accruals for property, plant and equipment additions	2,815	47
Ferrellgas, L.P. [Member]
Supplemental Financial Statement Information [Line Items]
Interest Paid	67,546	63,286
Income Taxes Paid	9	1
Noncash Investing and Financing Items [Abstract]
Liabilities incurred in connection with acquisitions	1,174	1,508
Change in accruals for property, plant and equipment additions	$ 2,815	$ 47