Consolidated Statements of Operations Statement (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Operating revenue	$ 1,327	$ 1,198	$ 3,671	$ 3,408
Operating costs and expenses:
Energy costs	489	428	1,338	1,182
Operations and maintenance	258	263	827	811
Depreciation and amortization	161	151	478	456
Taxes, other than income taxes	41	40	121	113
Total operating costs and expenses	949	882	2,764	2,562
Operating income	378	316	907	846
Other income (expense):
Interest expense	(94)	(102)	(284)	(297)
Allowance for borrowed funds	7	7	22	18
Allowance for equity funds	14	12	44	34
Interest income	1	1	2	5
Other, net	1	(2)	2	(3)
Total other income (expense)	(71)	(84)	(214)	(243)
Income before income tax expense	307	232	693	603
Income tax expense	95	63	200	178
Net income	$ 212	$ 169	$ 493	$ 425