Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment [Table Text Block]

Property, plant and equipment includes the following:

		December 31, 2019						December 31, 2018
	Weighted Average Useful Lives	Property, Plant and Equipment, Gross		Accumulated Depreciation & Amortization		Property, Plant and Equipment, Net		Property, Plant and Equipment, Gross		Accumulated Depreciation & Amortization		Property, Plant and Equipment, Net
	(in years)	(in millions)
CenterPoint Energy
Electric Transmission & Distribution	37	$	14,360	$	4,634	$	9,726	$	12,148	$	3,746	$	8,402
Electric Generation (1)	27	1,780		698		1,082		—		—		—
Natural Gas Distribution	29	12,787		3,766		9,021		7,345		2,159		5,186
Other property	19	1,397		602		795		741		306		435
Total		$	30,324	$	9,700	$	20,624	$	20,234	$	6,211	$	14,023
Houston Electric
Electric Transmission	46	$	3,358	$	674	$	2,684	$	3,077	$	650	$	2,427
Electric Distribution	35	7,876		2,586		5,290		7,524		2,553		4,971
Other transmission & distribution property	19	1,595		537		1,058		1,547		543		1,004
Total		$	12,829	$	3,797	$	9,032	$	12,148	$	3,746	$	8,402
CERC
Natural Gas Distribution	29	$	8,024	$	2,243	$	5,781	$	7,345	$	2,159	$	5,186
Other property	16	55		27		28		53		34		19
Total		$	8,079	$	2,270	$	5,809	$	7,398	$	2,193	$	5,205

(1) SIGECO and AGC own a 300 MW unit at the Warrick Power Plant (Warrick Unit 4) as tenants in common. SIGECO’s share of the cost of this unit as of December 31, 2019, is $194 million with accumulated depreciation totaling $137 million. AGC and SIGECO share equally in the cost of operation and output of the unit. SIGECO’s share of operating costs is included in Operation and maintenance expense in CenterPoint Energy’s Statements of Consolidated Income.

Depreciation and Amortization [Table Text Block]

The following table has been recast to exclude the Infrastructure Services and Energy Services Disposal Groups and presents depreciation and amortization expense for continuing operations for 2019, 2018 and 2017:

	Year Ended December 31,
	2019						2018						2017
	CenterPoint Energy		Houston Electric		CERC		CenterPoint Energy		Houston Electric		CERC		CenterPoint Energy		Houston Electric		CERC
	(in millions)
Depreciation	$	879	$	339	$	277	$	623	$	342	$	261	$	618	$	354	$	242
Amortization of securitized regulatory assets	271		271		—		531		531		—		329		329		—
Other amortization	75		38		16		76		44		19		73		41		21
Total	$	1,225	$	648	$	293	$	1,230	$	917	$	280	$	1,020	$	724	$	263

Asset Retirement Obligation [Table Text Block]

A reconciliation of the changes in the ARO liability recorded in Other non-current liabilities on each of the Registrants’ respective Consolidated Balance Sheets is as follows:

	December 31, 2019						December 31, 2018
	CenterPoint Energy		Houston Electric		CERC		CenterPoint Energy			Houston Electric			CERC
	(in millions)
Beginning balance	$	258	$	34	$	221	$	281		$	35		$	243
Addition from Merger with Vectren	116		—		—		—			—			—
Accretion expense (1)	16		1		10		10			1			9
Revisions in estimates (2)	149		7		94		(33		)	(2		)	(31		)
Ending balance	$	539	$	42	$	325	$	258		$	34		$	221

(1) Reflected in Regulatory assets on each of the Registrants’ respective Consolidated Balance Sheets.

(2)

In 2019, the Registrants reflected an increase in their respective ARO liability, which is primarily attributable to decreases in the long-term interest rates used for discounting in the ARO calculation and increased estimated closure costs for CenterPoint Energy’s electric generation. In 2018, CenterPoint Energy and CERC reflected a decrease in their respective ARO liability, which is primarily attributable to increases in the long-term interest rates used for discounting in the ARO calculation.