Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2018

Fair value, assets and liabilities measured on a recurring basis [Table Text Block]

The following tables present information about the Registrants’ assets and liabilities (including derivatives that are presented net) measured at fair value on a recurring basis and indicate the fair value hierarchy of the valuation techniques utilized by the Registrants to determine such fair value.

CenterPoint Energy



	June 30, 2018											December 31, 2017
	Level 1		Level 2		Level 3		Netting (1)			Total		Level 1		Level 2		Level 3		Netting (1)			Total
Assets	(in millions)
Corporate equities	$	586	$	—	$	—	$	—		$	586	$	963	$	—	$	—	$	—		$	963
Investments, including money market funds (2)	70		—		—		—			70		68		—		—		—			68
Natural gas derivatives (3)	—		142		18		(40		)	120		—		161		57		(64		)	154
Hedged portion of natural gas inventory	—		—		—		—			—		14		—		—		—			14
Total assets	$	656	$	142	$	18	$	(40	)	$	776	$	1,045	$	161	$	57	$	(64	)	$	1,199
Liabilities
Indexed debt securities derivative	$	—	$	—	$	641	$	—		$	641	$	—	$	—	$	668	$	—		$	668
Natural gas derivatives (3)	—		105		5		(72		)	38		—		96		11		(83		)	24
Hedged portion of natural gas inventory	1		—		—		—			1		—		—		—		—			—
Total liabilities	$	1	$	105	$	646	$	(72	)	$	680	$	—	$	96	$	679	$	(83	)	$	692

Houston Electric



	June 30, 2018										December 31, 2017
	Level 1		Level 2		Level 3		Netting		Total		Level 1		Level 2		Level 3		Netting		Total
Assets	(in millions)
Investments, including money market funds (2)	$	52	$	—	$	—	$	—	$	52	$	51	$	—	$	—	$	—	$	51
Total assets	$	52	$	—	$	—	$	—	$	52	$	51	$	—	$	—	$	—	$	51

CERC



	June 30, 2018											December 31, 2017
	Level 1		Level 2		Level 3		Netting (1)			Total		Level 1		Level 2		Level 3		Netting (1)			Total
Assets	(in millions)
Corporate equities	$	2	$	—	$	—	$	—		$	2	$	3	$	—	$	—	$	—		$	3
Investments, including money market funds (2)	11		—		—		—			11		11		—		—		—			11
Natural gas derivatives (3)	—		142		18		(40		)	120		—		161		57		(64		)	154
Hedged portion of natural gas inventory	—		—		—		—			—		14		—		—		—			14
Total assets	$	13	$	142	$	18	$	(40	)	$	133	$	28	$	161	$	57	$	(64	)	$	182
Liabilities
Natural gas derivatives (3)	$	—	$	105	$	5	$	(72	)	$	38	$	—	$	96	$	11	$	(83	)	$	24
Hedged portion of natural gas inventory	1		—		—		—			1		—		—		—		—			—
Total liabilities	$	1	$	105	$	5	$	(72	)	$	39	$	—	$	96	$	11	$	(83	)	$	24


(1)	Amounts represent the impact of legally enforceable master netting arrangements that allow CenterPoint Energy and CERC to settle positive and negative positions and also include cash collateral of $32 million and $19 million as of June 30, 2018 and December 31, 2017, respectively, posted with the same counterparties.


(2)	Amounts are included in Prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets.


(3)	Natural gas derivatives include no material amounts related to physical forward transactions with Enable.

Assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs [Table Text Block]

The following table presents additional information about assets or liabilities, including derivatives that are measured at fair value on a recurring basis for which CenterPoint Energy and CERC have utilized Level 3 inputs to determine fair value:



	Three Months Ended June 30,												Six Months Ended June 30,
	2018						2017						2018						2017
	CenterPoint Energy			CERC			CenterPoint Energy			CERC			CenterPoint Energy			CERC			CenterPoint Energy			CERC
	(in millions)
Beginning balance	$	(662	)	$	12		$	(700	)	$	27		$	(622	)	$	46		$	(704	)	$	13
Total gains (losses)	(11		)	1			(6		)	7			(16		)	3			—			23
Total settlements	44			(1		)	—			—			11			(35		)	(4		)	(4		)
Transfers into Level 3	1			1			1			1			1			1			2			2
Transfers out of Level 3	—			—			(7		)	(7		)	(2		)	(2		)	(6		)	(6		)
Ending balance (1)	$	(628	)	$	13		$	(712	)	$	28		$	(628	)	$	13		$	(712	)	$	28

The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or losses relating to assets still held at the reporting date:
	$	(9	)	$	3		$	(9	)	$	4		$	(23	)	$	(4	)	$	(2	)	$	21


(1)	CenterPoint Energy and CERC did not have significant Level 3 sales or purchases during either of the three or six months ended June 30, 2018 or 2017.

Estimated fair value of financial instruments, debt instruments [Table Text Block]

The fair values of cash and cash equivalents, investments in debt and equity securities classified as “trading” and short-term borrowings are estimated to be approximately equivalent to carrying amounts and have been excluded from the table below. The carrying amounts of non-trading derivative assets and liabilities and CenterPoint Energy’s ZENS indexed debt securities derivative are stated at fair value and are excluded from the table below. The fair value of each debt instrument is determined by multiplying the principal amount of each debt instrument by a combination of historical trading prices and comparable issue data. These liabilities, which are not measured at fair value in the Registrants’ Condensed Consolidated Balance Sheets, but for which the fair value is disclosed, would be classified as Level 2 in the fair value hierarchy.



	June 30, 2018						December 31, 2017
	CenterPoint Energy (1)		Houston Electric (1)		CERC		CenterPoint Energy (1)		Houston Electric (1)		CERC
Long-term debt, including current maturities	(in millions)
Carrying amount	$	8,256	$	4,919	$	2,722	$	8,679	$	4,753	$	2,457
Fair value	8,470		4,991		2,876		9,220		5,034		2,708


(1)	Includes Securitization Bond debt.