Income Taxes

9 Months Ended

Sep. 30, 2012

Income Tax Disclosure [Abstract]

Income Tax Disclosure [Text Block]

Income Taxes

The effective tax rate for the three and nine months ended September 30, 2012 was 25% and 28%, respectively, compared to 32% and 33% for the same periods in 2011. The decrease in the effective tax rate for the three and nine months ended September 30, 2012 was primarily due to favorable tax adjustments, including the re-measurement of certain unrecognized tax benefits, of $17 million and $25 million for the three and nine months ended September 30, 2012, respectively, related to CenterPoint Energy's Internal Revenue Service (IRS) settlement of tax years 2006 through 2009.

The following table summarizes CenterPoint Houston’s unrecognized tax benefits at December 31, 2011 and September 30, 2012:

	December 31, 2011		September 30, 2012
	(in millions)
Unrecognized tax benefits	$	44	$	—
Portion of unrecognized tax benefits that, if recognized, would reduce the effective income tax rate	18		—
Interest accrued on unrecognized tax benefits	5		—

CenterPoint Energy has a tentative settlement with the IRS for tax years 2008 and 2009 that is under review by the Joint Committee on Taxation. In September 2012, the IRS commenced its examination of CenterPoint Energy’s 2011 consolidated federal income tax return in conjunction with its review of CenterPoint Energy's 2010 consolidated federal income tax return.