Schedule I Parent Only Balance Sheets, Statements Of Earnings And Cash Flows (Statement Of Earnings) (Details) (USD $)	12 Months Ended
	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Operating expense	$ 411,038,000	$ 409,014,000	$ 400,735,000
Operating income (loss)	105,761,000	158,363,000	146,487,000
Interest expense	(101,885,000)	(101,284,000)	(89,519,000)
Loss on extinguishment of debt	(46,962,000)	(20,716,000)
Other income (expense), net	567,000	(1,108,000)	(1,321,000)
Income tax expense	1,241,000	1,916,000	2,292,000
Net earnings (loss)	(43,760,000)	33,339,000	53,355,000
Parent Company [Member]
Equity in (earnings) loss of Ferrellgas, L.P.	(10,950,000)	61,731,000	76,718,000
Operating expense	(358,000)	(424,000)	(328,000)
Operating income (loss)	(11,308,000)	61,307,000	76,390,000
Interest expense	(21,811,000)	(24,498,000)	(23,734,000)
Loss on extinguishment of debt	(10,513,000)	(3,408,000)
Other income (expense), net		(666,000)
Income tax expense	(16,000)	(26,000)	(84,000)
Net earnings (loss)	$ (43,648,000)	$ 32,709,000	$ 52,572,000