CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Operating revenues:
Electric, natural gas distribution and pipeline and energy services	$ 274,538	$ 272,177	$ 752,018	$ 732,422
Construction services, natural gas and oil production, construction materials and contracting, and other	656,219	634,267	1,080,544	1,008,799
Total operating revenues	930,757	906,444	1,832,562	1,741,221
Operating expenses:
Fuel and purchased power	14,474	13,106	31,428	30,017
Purchased natural gas sold	101,538	97,441	346,224	331,133
Operation and maintenance:
Electric, natural gas distribution and pipeline and energy services	70,028	68,437	137,989	131,421
Construction services, natural gas and oil production, construction materials and contracting, and other	536,608	516,854	896,408	830,642
Depreciation, depletion and amortization	83,290	81,547	167,964	160,225
Taxes, other than income	42,516	40,397	92,181	86,192
Total operating expenses	848,454	817,782	1,672,194	1,569,630
Operating income	82,303	88,662	160,368	171,591
Earnings from equity method investments	949	2,260	1,433	4,443
Other income	1,908	2,686	3,809	5,188
Interest expense	20,036	20,490	42,053	41,006
Income before income taxes	65,124	73,118	123,557	140,216
Income taxes	19,889	24,180	35,793	49,506
Income from continuing operations	45,235	48,938	87,764	90,710
Income (loss) from discontinued operations, net of tax (Note 9)	(168)	0	280	0
Net income	45,067	48,938	88,044	90,710
Dividends on preferred stocks	171	171	342	343
Earnings on common stock	$ 44,896	$ 48,767	$ 87,702	$ 90,367
Earnings per common share - basic:
Earnings before discontinued operations	$ 0.24	$ 0.26	$ 0.46	$ 0.48
Discontinued operations, net of tax	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Earnings per common share -- basic	$ 0.24	$ 0.26	$ 0.46	$ 0.48
Earnings per common share - diluted:
Earnings before discontinued operations	$ 0.24	$ 0.26	$ 0.46	$ 0.48
Discontinued operations, net of tax	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Earnings per common share -- diluted	$ 0.24	$ 0.26	$ 0.46	$ 0.48
Dividends per common share	$ 0.1625	$ 0.1575	$ 0.3250	$ 0.3150
Weighted average common shares outstanding -- basic	188,794	188,129	188,732	188,047
Weighted average common shares outstanding -- diluted	188,968	188,267	188,903	188,198