CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating revenues
Electric	$ 1,936,782	$ 2,029,972
Natural gas	621,035	765,349
Other	20,262	21,219
Total operating revenues	2,578,079	2,816,540
Operating expenses
Electric fuel and purchased power	863,980	931,828
Cost of natural gas sold and transported	417,946	543,376
Cost of sales - other	7,304	8,055
Operating and maintenance expenses	510,684	510,027
Conservation and demand side management program expenses	63,707	75,298
Depreciation and amortization	228,672	224,723
Taxes (other than income taxes)	105,624	96,570
Total operating expenses	2,197,917	2,389,877
Operating income	380,162	426,663
Other income, net	3,737	4,766
Equity earnings of unconsolidated subsidiaries	7,158	7,713
Allowance for funds used during construction - equity	13,450	13,244
Interest charges and financing costs
Interest charges - includes other financing costs of $6,080 and $5,260, respectively	151,830	144,354
Allowance for funds used during construction - debt	(6,607)	(7,436)
Total interest charges and financing costs	145,223	136,918
Income from continuing operations before income taxes	259,284	315,468
Income taxes	75,515	112,001
Income from continuing operations	183,769	203,467
Income from discontinued operations, net of tax	124	102
Net income	183,893	203,569
Dividend requirements on preferred stock	0	1,060
Earnings available to common shareholders	$ 183,893	$ 202,509
Weighted average common shares outstanding:
Basic (in shares)	487,360	483,641
Diluted (in shares)	487,995	484,301
Earnings per average common share:
Basic (in dollars per share)	$ 0.38	$ 0.42
Diluted (in dollars per share)	$ 0.38	$ 0.42
Cash dividends declared per common share (in dollars per share)	$ 0.26	$ 0.25