Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating revenues:
Electric, natural gas distribution and regulated pipeline and midstream	$ 1,148,272	$ 1,246,646	$ 1,156,838
Nonregulated pipeline and midstream, construction materials and contracting, construction services, refining and other	3,043,277	2,868,170	2,763,333
Total operating revenues	4,191,549	4,114,816	3,920,171
Operating expenses:
Fuel and purchased power	86,238	89,312	83,528
Purchased natural gas sold	450,114	558,463	495,471
Cost of crude oil	159,811	0	0
Operation and maintenance:
Electric, natural gas distribution and regulated pipeline and midstream	277,638	269,225	253,214
Nonregulated pipeline and midstream, construction materials and contracting, construction services, refining and other	2,593,300	2,529,020	2,426,145
Depreciation, depletion and amortization	227,730	203,980	200,398
Taxes, other than income	142,585	145,393	140,713
Total operating expenses	3,937,416	3,795,393	3,599,469
Operating income	254,133	319,423	320,702
Other income	19,232	9,873	6,086
Interest expense	93,068	86,906	83,803
Income before income taxes	180,297	242,390	242,985
Income taxes	65,603	63,227	74,294
Income from continuing operations	114,694	179,163	168,691
Income (loss) from discontinued operations, net of tax (Note 2)	(772,385)	115,175	109,879
Net income (loss)	(657,691)	294,338	278,570
Net loss attributable to noncontrolling interest	(35,256)	(3,895)	(363)
Dividends declared on preferred stocks	685	685	685
Earnings (loss) on common stock	$ (623,120)	$ 297,548	$ 278,248
Earnings (loss) per common share - basic:
Earnings before discontinued operations	$ 0.77	$ 0.95	$ 0.89
Discontinued operations, net of tax	(3.97)	0.60	0.58
Earnings (loss) per common share - basic	(3.20)	1.55	1.47
Earnings (loss) per common share - diluted:
Earnings before discontinued operations	0.77	0.95	0.89
Discontinued operations, net of tax	(3.97)	0.60	0.58
Earnings (loss) per common share - diluted	$ (3.20)	$ 1.55	$ 1.47
Weighted average common shares outstanding - basic	194,928	192,507	188,855
Weighted average common shares outstanding - diluted	194,986	192,587	189,693