Contingencies And Commitments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011
Transportation Equipment [Member]
Transportation equipment lease expiration period	5 years
Guarantees Residual Value, Fair Value Disclosure	$ 0.9
Guarantor Obligations, Maximum Exposure, Undiscounted	4.1
Transportation Equipment [Member] | Ferrellgas, L.P. [Member]
Transportation equipment lease expiration period	5 years
Guarantees Residual Value, Fair Value Disclosure	0.9
Guarantor Obligations, Maximum Exposure, Undiscounted	4.1
Property And Equipment [Member]
Non-cancelable operating leases, expiration year	2024
Rental expense	32.2	31.7	33.3
Property And Equipment [Member] | Ferrellgas, L.P. [Member]
Non-cancelable operating leases, expiration year	2024
Rental expense	$ 32.2	$ 31.7	$ 33.3