Debt (Secured Credit Facility Narrative) (Details) (USD $)																																								12 Months Ended			12 Months Ended							12 Months Ended				12 Months Ended
	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Minimum [Member] Eurodollar Rate Loan [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Minimum [Member] Euro Rate [Member]	Jul. 31, 2011 Minimum [Member] Eurodollar Rate Loan [Member]	Jul. 31, 2011 Minimum [Member] Euro Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Maximum [Member] Eurodollar Rate Loan [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Maximum [Member] Euro Rate [Member]	Jul. 31, 2011 Maximum [Member] Eurodollar Rate Loan [Member]	Jul. 31, 2011 Maximum [Member] Euro Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Federal Funds Rate [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Federal Funds Rate [Member]	Dec. 31, 2011 Federal Funds Rate [Member]	Jul. 31, 2011 Federal Funds Rate [Member]	Jul. 31, 2010 Federal Funds Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Swing Line Loans [Member]	Jul. 31, 2011 Swing Line Loans [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Eurodollar Rate Loan [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Eurodollar Rate Loan [Member]	Jul. 31, 2011 Eurodollar Rate Loan [Member]	Jul. 31, 2010 Eurodollar Rate Loan [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Euro Rate [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Euro Rate [Member]	Jul. 31, 2011 Euro Rate [Member]	Jul. 31, 2010 Euro Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Bank Of America's Prime Rate [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Bank Of America's Prime Rate [Member]	Dec. 31, 2011 Bank Of America's Prime Rate [Member]	Jul. 31, 2010 Bank Of America's Prime Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] One-Month Eurodollar Rate [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] One-Month Eurodollar Rate [Member]	Jul. 31, 2011 One-Month Eurodollar Rate [Member]	Jul. 31, 2010 One-Month Eurodollar Rate [Member]	Dec. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Three-Month Eurodollar Rate [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Three-Month Eurodollar Rate [Member]	Jul. 31, 2011 Three-Month Eurodollar Rate [Member]	Jul. 31, 2010 Three-Month Eurodollar Rate [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Secure Insurance Arrangements [Member] Letter Of Credit [Member]	Jul. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Secure Insurance Arrangements [Member] Letter Of Credit [Member]	Jul. 31, 2011 Secure Insurance Arrangements [Member] Letter Of Credit [Member]	Jul. 31, 2010 Secure Insurance Arrangements [Member] Letter Of Credit [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Secured Facility Due November 2012 [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member]	Jul. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2009 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2011 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member]	Dec. 31, 2010 Ferrellgas, L.P. And Subsidiaries [Member] Secured Credit Facility [Member]	Jul. 31, 2011 Secured Credit Facility [Member]	Jul. 31, 2010 Secured Credit Facility [Member]	Jul. 31, 2011 Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2010 Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2009 Secured Credit Facility [Member] Letter Of Credit [Member]	Jul. 31, 2010 Secured Credit Facility [Member]	Jul. 31, 2011 Secured Credit Facility [Member]	Jul. 31, 2010 Secured Credit Facility [Member]
Secured line of credit facility																																									$ 400,000,000		$ 200,000,000					$ 400,000,000		$ 200,000,000
Debt instrument, maturity date																																								November 2012														November 2012
Line of credit facility																																										167,000,000				129,500,000							167,000,000	129,500,000
Amount classified as long-term debt																																										99,800,000				64,600,000							99,800,000	64,600,000
Weighted average interest rate of debt																																														6.53%	5.91%		5.91%					6.53%
Weighted average interest rate of debt																																																						9.20%	9.50%
Debt instrument, basis spread rate	3.50%	2.50%	3.50%	2.50%	4.25%	3.25%	4.25%	3.25%	0.50%			0.50%	0.18%	1.00%	1.00%	4.00%	3.75%	4.00%	3.75%	3.00%	2.75%	3.00%	2.75%				3.25%
Credit facility interest rate									0.11%	0.18%	0.11%													3.25%	3.25%	3.25%		0.22%	0.40%	0.22%	0.40%	0.34%	0.60%	0.34%	0.60%
Commitment fee payable rate																																														0.50%								0.50%
Letter of credit outstanding																																				47,500,000	47,100,000	47,500,000	47,100,000
Letter of credit facility, remaining capacity																																											152,500,000	152,900,000						152,500,000	152,900,000
Line of credit facility, commitment fee																																											$ 1,100,000	$ 900,000	$ 900,000					$ 1,100,000	$ 900,000	$ 900,000