Goodwill and other intangible assets (Tables)

9 Months Ended

Sep. 30, 2011

Goodwill and other intangible assets [Abstract]

Changes in the Carrying Amount of Goodwill

The changes in the carrying amount of goodwill were as follows:

	Balance		Goodwill		Balance
	as of		Acquired		as of
Nine Months Ended	January 1,		During		September 30,
September 30, 2011		2011*	the Year**			2011*
	(In thousands)
Electric	$	-	$	-	$	-
Natural gas distribution		345,736		-		345,736
Construction services		102,870		298		103,168
Pipeline and energy services		9,737		-		9,737
Natural gas and oil production		-		-		-
Construction materials and contracting		176,290		-		176,290
Other		-		-		-
Total	$	634,633	$	298	$	634,931
*Balance is presented net of accumulated impairment of $12.3 million at the pipeline and energy services segment, which occurred in prior periods. **Includes a purchase price adjustment that was not material related to an acquisition in a prior period.

Nine Months Ended September 30, 2010	Balance as of January 1, 2010*		Goodwill Acquired During the Year**		Balance as of September 30, 2010*
	(In thousands)
Electric	$	-	$	-	$	-
Natural gas distribution		345,736		-		345,736
Construction services		100,127		2,743		102,870
Pipeline and energy services		7,857		1,880		9,737
Natural gas and oil production		-		-		-
Construction materials and contracting		175,743		547		176,290
Other		-		-		-
Total	$	629,463	$	5,170	$	634,633
*Balance is presented net of accumulated impairment of $12.3 million at the pipeline and energy services segment, which occurred in prior periods. **Includes purchase price adjustments that were not material related to acquisitions in a prior period.

	Balance		Goodwill		Balance
	as of		Acquired		as of
Year Ended	January 1,		During the		December 31,
December 31, 2010		2010*	Year**			2010*
	(In thousands)
Electric	$	-	$	-	$	-
Natural gas distribution		345,736		-		345,736
Construction services		100,127		2,743		102,870
Pipeline and energy services		7,857		1,880		9,737
Natural gas and oil production		-		-		-
Construction materials and contracting		175,743		547		176,290
Other		-		-		-
Total	$	629,463	$	5,170	$	634,633
*Balance is presented net of accumulated impairment of $12.3 million at the pipeline and energy services segment, which occurred in prior periods. **Includes purchase price adjustments that were not material related to acquisitions in a prior period.

Other Amortizable Intangible Assets

Other amortizable intangible assets were as follows:

	September 30, 2011			September 30, 2010			December 31, 2010
	(In thousands)
Customer relationships	$	21,702		$	24,942		$	24,942
Accumulated amortization		(9,896	)		(11,273	)		(11,625	)
		11,806			13,669			13,317
Noncompete agreements		7,685			9,405			9,405
Accumulated amortization		(5,222	)		(6,231	)		(6,425	)
		2,463			3,174			2,980
Other		12,901			13,217			13,217
Accumulated amortization		(4,922	)		(3,948	)		(4,243	)
		7,979			9,269			8,974
Total	$	22,248		$	26,112		$	25,271