Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2019

Commitments and Contingencies Disclosure [Abstract]

Long-term Purchase Commitment [Table Text Block]

As of June 30, 2019, minimum purchase obligations are approximately:

	CenterPoint Energy		CERC
	(in millions)
Remaining six months of 2019	$	399	$	276
2020	658		459
2021	488		308
2022	576		402
2023	350		197
2024	228		132
2025 and beyond	1,639		1,276

Schedule of Environmental Loss Contingencies by Site [Table Text Block]

Minnesota MGPs (CenterPoint Energy and CERC). With respect to certain Minnesota MGP sites, CenterPoint Energy and CERC have completed state-ordered remediation and continue state-ordered monitoring and water treatment. CenterPoint Energy and CERC recorded a liability as reflected in the table below for continued monitoring and any future remediation required by regulators in Minnesota. The estimated range of possible remediation costs for the sites for which CenterPoint Energy and CERC believe they may have responsibility was based on remediation continuing for the time frame given in the table below.

	June 30, 2019
	CenterPoint Energy		CERC
	(in millions, except years)
Amount accrued for remediation	$	7	$	7
Minimum estimated remediation costs	4		4
Maximum estimated remediation costs	32		32
Minimum years of remediation	30		30
Maximum years of remediation	50		50