Derivative Instruments and Hedging Activities (Fair Value of Financial Derivatives Balance Sheet Locations) (Details) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	$ 7,006	$ 2,532
Interest Rate Derivative Assets, at Fair Value	2,101	3,783
Derivative Asset, Fair Value, Gross Asset	9,107	6,315
Derivatives - Price risk management liabilities	83	907
Interest Rate Derivative Liabilities, at Fair Value	5,075	4,998
Derivative Liability, Fair Value, Gross Liability	5,158	5,905
Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	7,006	2,532
Interest Rate Derivative Assets, at Fair Value	2,101	3,783
Derivative Asset, Fair Value, Gross Asset	9,107	6,315
Derivatives - Price risk management liabilities	83	907
Interest Rate Derivative Liabilities, at Fair Value	5,075	4,998
Derivative Liability, Fair Value, Gross Liability	5,158	5,905
Prepaid Expenses And Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	5,301	1,400
Interest Rate Derivative Assets, at Fair Value	2,101	3,341
Prepaid Expenses And Other Current Assets [Member] | Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	5,301	1,400
Interest Rate Derivative Assets, at Fair Value	2,101	3,341
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management liabilities	83	569
Interest Rate Derivative Liabilities, at Fair Value	0	0
Other Current Liabilities [Member] | Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management liabilities	83	569
Interest Rate Derivative Liabilities, at Fair Value	0	0
Other Assets, Net [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	1,705	1,132
Interest Rate Derivative Assets, at Fair Value	0	442
Other Assets, Net [Member] | Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management assets	1,705	1,132
Interest Rate Derivative Assets, at Fair Value	0	442
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management liabilities	0	338
Interest Rate Derivative Liabilities, at Fair Value	5,075	4,998
Other Liabilities [Member] | Ferrellgas, L.P. [Member]
Derivatives, Fair Value [Line Items]
Derivatives - Price risk management liabilities	0	338
Interest Rate Derivative Liabilities, at Fair Value	$ 5,075	$ 4,998