Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2014

Defined Benefit Plan Disclosure [Line Items]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

CenterPoint Houston’s employees participate in CenterPoint Energy’s postretirement benefit plan. CenterPoint Houston’s net periodic cost includes the following components relating to postretirement benefits:

	Three Months Ended June 30,						Six Months Ended June 30,
	2014			2013			2014			2013
	(in millions)
Interest cost	$	3		$	4		$	7		$	7
Expected return on plan assets	(2		)	(2		)	(3		)	(3		)
Amortization of prior service credit	(1		)	—			(1		)	—
Amortization of loss	1			1			1			2
Amortization of transition obligation	1			1			2			2
Net periodic cost	$	2		$	4		$	6		$	8