Segment Information (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting [Abstract]

Schedule of Segment Reporting Information

The following tables present revenues from external customers, intersegment revenues, and segment net income (thousands of dollars):

	Natural Gas      Operations		Construction     Services		Total
Three months ended June 30, 2013
Revenues from external customers	$	238,869	$	150,434	$	389,303
Intersegment revenues		-		22,271		22,271
Total	$	238,869	$	172,705	$	411,574
Segment net income	$	1,964	$	8,144	$	10,108
Three months ended June 30, 2012
Revenues from external customers	$	255,917	$	134,402	$	390,319
Intersegment revenues		-		19,449		19,449
Total	$	255,917	$	153,851	$	409,768
Segment net income (loss)	$	(3,368)	$	(308)	$	(3,676)

	Natural Gas     Operations		Construction     Services		Total
Six months ended June 30, 2013
Revenues from external customers	$	732,469	$	255,300	$	987,769
Intersegment revenues		-		37,310		37,310
Total	$	732,469	$	292,610	$	1,025,079
Segment net income	$	81,256	$	9,625	$	90,881
Six months ended June 30, 2012
Revenues from external customers	$	786,630	$	245,289	$	1,031,919
Intersegment revenues		-		35,494		35,494
Total	$	786,630	$	280,783	$	1,067,413
Segment net income (loss)	$	75,998	$	(755)	$	75,243

	Natural Gas     Operations		Construction     Services		Total
Twelve months ended June 30, 2013
Revenues from external customers	$	1,267,567	$	532,687	$	1,800,254
Intersegment revenues		-		85,190		85,190
Total	$	1,267,567	$	617,877	$	1,885,444
Segment net income	$	121,877	$	27,092	$	148,969
Twelve months ended June 30, 2012
Revenues from external customers	$	1,362,729	$	479,051	$	1,841,780
Intersegment revenues		-		95,876		95,876
Total	$	1,362,729	$	574,927	$	1,937,656
Segment net income	$	99,204	$	15,722	$	114,926