Employee Benefits (Details) (USD $)	12 Months Ended
	Jul. 31, 2012 employee	Jul. 31, 2011	Jul. 31, 2010
Number of employees	0
Non-cash compensation charges	$ 9,440,000	$ 10,157,000	$ 9,322,000
Matching contributions	2,900,000	3,100,000	3,200,000
Other comprehensive income and other liabilities adjustment	38,000	200,000	46,000
Ferrellgas, L.P. [Member]
Number of employees	0
Non-cash compensation charges	9,440,000	10,157,000	9,322,000
Matching contributions	2,900,000	3,100,000	3,200,000
Other comprehensive income and other liabilities adjustment	$ 38,000	$ 200,000	$ 46,000