CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Operating revenues:
Electric, natural gas distribution and pipeline and energy services	$ 212,848	$ 223,602	$ 964,866	$ 956,025
Construction services, natural gas and oil production, construction materials and contracting, and other	939,333	902,321	2,019,877	1,911,119
Total operating revenues	1,152,181	1,125,923	2,984,743	2,867,144
Operating expenses:
Fuel and purchased power	17,357	15,283	48,784	45,300
Purchased natural gas sold	50,102	51,243	396,326	382,376
Operation and maintenance:
Electric, natural gas distribution and pipeline and energy services	69,475	95,367	207,465	226,788
Construction services, natural gas and oil production, construction materials and contracting, and other	767,519	732,998	1,663,927	1,563,640
Depreciation, depletion and amortization	88,897	84,841	256,861	245,066
Taxes, other than income	39,410	37,229	131,591	123,421
Total operating expenses	1,032,760	1,016,961	2,704,954	2,586,591
Operating income	119,421	108,962	279,789	280,553
Earnings from equity method investments	826	2,528	2,260	6,970
Other income	1,282	1,740	5,090	6,929
Interest expense	19,589	20,944	61,642	61,950
Income before income taxes	101,940	92,286	225,497	232,502
Income taxes	37,840	31,276	73,632	80,783
Income from continuing operations	64,100	61,010	151,865	151,719
Income (loss) from discontinued operations, net of tax (Note 9)	(126)	0	154	0
Net income	63,974	61,010	152,019	151,719
Dividends on preferred stocks	171	172	514	513
Earnings on common stock	$ 63,803	$ 60,838	$ 151,505	$ 151,206
Earnings per common share - basic:
Earnings before discontinued operations	$ 0.34	$ 0.32	$ 0.80	$ 0.80
Discontinued operations, net of tax	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Earnings per common share -- basic	$ 0.34	$ 0.32	$ 0.80	$ 0.80
Earnings per common share - diluted:
Earnings before discontinued operations	$ 0.34	$ 0.32	$ 0.80	$ 0.80
Discontinued operations, net of tax	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Earnings per common share -- diluted	$ 0.34	$ 0.32	$ 0.80	$ 0.80
Dividends per common share	$ 0.1625	$ 0.1575	$ 0.4875	$ 0.4725
Weighted average common shares outstanding -- basic	188,794	188,170	188,753	188,088
Weighted average common shares outstanding -- diluted	188,797	188,338	188,760	188,268