Derivative Instruments and Hedging Activities (Narrative) (Details) (USD $)	3 Months Ended
	Oct. 31, 2012 bbl	Oct. 31, 2011
Gain (loss) recognized in earnings related to hedge ineffectiveness	$ 0	$ 0
Reclassification of net gain to earnings during next 12 months	200,000
Reclassification of gain (loss) to earnings from discontinuance of cash flow hedges	0	0
Number of barrells of propane covered by cash flow hedges	1,400,000
Derivative amount of credit risk	2,800,000
Derivative, Net Liability Position, Aggregate Fair Value	800,000
Collateral Already Posted, Aggregate Fair Value	900,000
Additional Collateral, Aggregate Fair Value	0
Ferrellgas, L.P. [Member]
Gain (loss) recognized in earnings related to hedge ineffectiveness	0	0
Reclassification of net gain to earnings during next 12 months	200,000
Reclassification of gain (loss) to earnings from discontinuance of cash flow hedges	0	0
Number of barrells of propane covered by cash flow hedges	1,400,000
Derivative amount of credit risk	2,800,000
Derivative, Net Liability Position, Aggregate Fair Value	800,000
Collateral Already Posted, Aggregate Fair Value	900,000
Additional Collateral, Aggregate Fair Value	$ 0