Fair Value Measurements

12 Months Ended

Dec. 31, 2011

Fair Value Measurements [Abstract]

Fair Value Disclosures [Text Block]

Fair Value Measurements

Assets and liabilities are recorded at fair value in the Consolidated Balance Sheets and are categorized based upon the level of judgment associated with the inputs used to measure their value. Hierarchical levels, as defined below and directly related to the amount of subjectivity associated with the inputs to fair valuations of these assets and liabilities, are as follows:

Level 1: Inputs are unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date. The types of assets carried at Level 1 fair value are investments listed in active markets.  At December 31, 2010 and 2011, CenterPoint Houston held Level 1 investments of $36 million and $38 million, respectively, which were primarily money market funds.

Level 2:  Inputs, other than quoted prices included in Level 1, are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar instruments in active markets, and inputs other than quoted prices that are observable for the asset or liability. CenterPoint Houston had no Level 2 assets or liabilities at either December 31, 2010 or 2011.

Level 3: Inputs are unobservable for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. These inputs reflect management’s best estimate of the assumptions market participants would use in determining fair value.  CenterPoint Houston had no Level 3 assets or liabilities at either December 31, 2010 or 2011.

Estimated Fair Value of Financial Instruments

The fair values of cash and cash equivalents, short-term borrowings and the $750 million notes receivable from CenterPoint Houston’s parent are estimated to be equivalent to carrying amounts and have been excluded from the table below.  The fair value of each debt instrument is determined by multiplying the principal amount of each debt instrument by the market price.

	December 31, 2010				December 31, 2011
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(in millions)
Financial liabilities:
Long-term debt (including $151 million of long-term notes payable to parent)	$	5,048	$	5,499	$	4,765	$	5,345