Supplemental Financial Statement Information (Loss On Disposal Of Assets And Other) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Loss on disposal of assets	$ 6,035	$ 3,633	$ 7,296
Loss on transfer of accounts receivable related to the accounts receivable securitization			6,566
Service income related to the accounts receivable securitization			(5,377)
Loss on disposal of assets and other	6,035	3,633	8,485
Ferrellgas, L.P. [Member]
Loss on disposal of assets	6,035	3,633	7,296
Loss on transfer of accounts receivable related to the accounts receivable securitization			6,566
Service income related to the accounts receivable securitization			(5,377)
Loss on disposal of assets and other	$ 6,035	$ 3,633	$ 8,485