Supplemental Information - Cash (Details) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jul. 31, 2020	Jul. 31, 2019
Supplemental Financial Statement Information [Line Items]
Cash and cash equivalents	$ 217,434		$ 238,002
Restricted cash	109,049		95,759
Cash pledged as collateral for letters of credit	91,500		78,200
Cash deposit against contingencies	11,500		11,500
Additional pledged collateral	6,000		6,100
Cash and cash equivalents and restricted cash	326,483	$ 13,706	333,761	$ 11,054
Cash paid for interest	88,107	83,826
Income taxes	305	1
Noncash Investing and Financing Items [Abstract]
Liability incurred in connection with Financing Agreement amendment		8,863
Liabilities incurred in connection with acquisitions		520
Change in accruals for property, plant and equipment additions	(178)	268
Lease liabilities arising from operating right-of-use assets	4,262	21,606
Lease liabilities arising from finance right-of-use assets	972	12,241
Ferrellgas, L.P. [Member]
Supplemental Financial Statement Information [Line Items]
Cash and cash equivalents	197,528		237,996
Restricted cash	109,049		95,759
Cash pledged as collateral for letters of credit	91,500		78,200
Cash deposit against contingencies	11,500		11,500
Additional pledged collateral	6,000		6,100
Cash and cash equivalents and restricted cash	306,577	13,643	$ 333,755	$ 11,046
Cash paid for interest	88,107	68,430
Income taxes	290	1
Noncash Investing and Financing Items [Abstract]
Liability incurred in connection with Financing Agreement amendment		8,863
Liabilities incurred in connection with acquisitions		520
Change in accruals for property, plant and equipment additions	(178)	268
Lease liabilities arising from operating right-of-use assets	4,262	21,606
Lease liabilities arising from finance right-of-use assets	$ 972	$ 12,241