Goodwill (Tables)

12 Months Ended

Dec. 31, 2012

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Goodwill by reportable business segment as of December 31, 2011 and 2012 is as follows (in millions):

	December 31, 2011		Impairment Charge		Acquisition		December 31, 2012
Natural Gas Distribution	$	746	$	—	$	—	$	746
Interstate Pipelines	579		—		—		579
Competitive Natural Gas Sales and Services	335		252		—		83
Field Services	25		—		24		49
Other Operations	11		—		—		11
Total	$	1,696	$	252	$	24	$	1,468