Income Taxes	6 Months Ended
Jun. 30, 2013
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes The effective tax rate for the three and six months ended June 30, 2013 was 37% and 36%, respectively, compared to 38% and 31% for the same period in 2012. The lower effective tax rate for the six months ended June 30, 2012 was primarily due to a $10 million reduction to the uncertain tax liability related to a settlement with the Internal Revenue Service (IRS) of CenterPoint Energy's consolidated federal income tax returns for tax years 2006 and 2007. CenterPoint Houston has recognized the financial statement effects of all tax positions when it is more likely than not, based on the technical merits, that the positions would be sustained upon examination. CenterPoint Houston did not have any uncertain tax positions as of June 30, 2013. CenterPoint Energy's consolidated federal income tax returns have been audited by the IRS and settled through the 2009 tax year. CenterPoint Energy has filed claims for income tax refunds that are pending review by the IRS for tax years 2002, 2003 and 2004. CenterPoint Energy is currently under examination by the IRS for tax years 2010 and 2011. CenterPoint Energy has considered the effects of these examinations in its accrual for settled issues and liability for uncertain income tax positions as of June 30, 2013. On July 9, 2013, CenterPoint Energy received notification that the Joint Committee of Taxation had approved its outstanding tax claims related to the 2002 and 2003 audit cycles. CenterPoint Energy will record the effects of the settlement in the third quarter of 2013.

Income Taxes

6 Months Ended

Jun. 30, 2013

Income Taxes

The effective tax rate for the three and six months ended June 30, 2013 was 37% and 36%, respectively, compared to 38% and 31% for the same period in 2012. The lower effective tax rate for the six months ended June 30, 2012 was primarily due to a $10 million reduction to the uncertain tax liability related to a settlement with the Internal Revenue Service (IRS) of CenterPoint Energy's consolidated federal income tax returns for tax years 2006 and 2007.

CenterPoint Houston has recognized the financial statement effects of all tax positions when it is more likely than not, based on the technical merits, that the positions would be sustained upon examination. CenterPoint Houston did not have any uncertain tax positions as of June 30, 2013.

CenterPoint Energy's consolidated federal income tax returns have been audited by the IRS and settled through the 2009 tax year. CenterPoint Energy has filed claims for income tax refunds that are pending review by the IRS for tax years 2002, 2003 and 2004. CenterPoint Energy is currently under examination by the IRS for tax years 2010 and 2011. CenterPoint Energy has considered the effects of these examinations in its accrual for settled issues and liability for uncertain income tax positions as of June 30, 2013.

On July 9, 2013, CenterPoint Energy received notification that the Joint Committee of Taxation had approved its outstanding tax claims related to the 2002 and 2003 audit cycles. CenterPoint Energy will record the effects of the settlement in the third quarter of 2013.