Disclosures About Derivative Instruments Hedging Activities (Details 1) (USD $) In Thousands	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI and Noncontrolling Interests	$ 22,275	$ 37,568	$ (138,317)
Gain (Loss) Reclassified from AOCI and Noncontrolling Interest into Income	32,243	25,629	(195,851)
Propane contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI and Noncontrolling Interests	22,275	35,829	(128,213)
Propane contracts [Member] | Cost of sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI and Noncontrolling Interest into Income	35,292	38,360	(193,364)
Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in AOCI and Noncontrolling Interests	0	1,739	(10,104)
Interest rate contracts [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI and Noncontrolling Interest into Income	$ (3,049)	$ (12,731)	$ (2,487)