CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Operating revenues
Sales of electricity	$ 11,086	$ 11,723	$ 10,713
Other revenue	134	118	161
Total operating revenues	11,220	11,841	10,874
Operating expenses
Fuel	2,680	2,926	2,092
Purchased power	1,189	1,427	1,127
Operating and maintenance	3,510	3,617	3,232
Depreciation and amortization	1,919	1,772	1,724
Tax equivalents	622	662	457
Total operating expenses	9,920	10,404	8,632
Operating income	1,300	1,437	2,242
Other income (expense), net	33	30	24
Interest expense
Interest expense	1,444	1,431	1,373
Allowance for funds used during construction and nuclear fuel expenditures	(171)	(126)	(79)
Net interest expense	1,273	1,305	1,294
Net income (loss)	$ 60	$ 162	$ 972