Supplemental Financial Statement Information Supplemental Financial Statement Information (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Property, Plant and Equipment, Additions	$ 164	$ (1,122)	$ 498
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	139	2,126	481
Issuance of common units in connection with acquisitions		(46,432)	265,639
Income Taxes Paid	310	777	712
Interest Paid	143,441	133,629	91,783
Common Unitholders [Member]
Issuance of common units in connection with acquisitions		(45,968)	262,952
Assets [Member] | Common Unitholders [Member]
Issuance of common units in connection with acquisitions	0	0	262,952
Ferrellgas, L.P. [Member]
Property, Plant and Equipment, Additions	164	(1,122)	498
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	139	2,126	481
Issuance of common units in connection with acquisitions	167,843	(284)	833,875
Income Taxes Paid	305	773	643
Interest Paid	122,084	117,931	76,085
Ferrellgas, L.P. [Member] | Common Unitholders [Member]
Issuance of common units in connection with acquisitions	166,148	(284)	825,452
Ferrellgas, L.P. [Member] | Assets [Member] | Common Unitholders [Member]
Issuance of common units in connection with acquisitions	$ 0	$ 0	$ 825,452