General mortgage bonds used as collateral

No definition available.

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- Definition

Percentage on limitation of debt to total capitalization under covenant.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Long-term Debt (Details) (USD $) In Millions, unless otherwise specified				0 Months Ended		0 Months Ended										9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Mar. 17, 2014 Bonds General Mortgage Due 2044 [Member]	Mar. 03, 2014 Secured Debt [Member] Bonds Pollution Control Due2027 [Member]	Mar. 03, 2014 Secured Debt [Member] Bonds Pollution Control Due2027 [Member]	Jun. 02, 2014 Secured Debt [Member] Bonds Pollution Control Due2017 [Member]	Mar. 03, 2014 Secured Debt [Member] Bonds Pollution Control Due2017 [Member]	Jun. 02, 2014 Secured Debt [Member] Bonds Pollution Control Due2017 [Member]	Mar. 03, 2014 Secured Debt [Member] Bonds Pollution Control Due2017 [Member]	Sep. 30, 2014 CenterPoint Energy [Member]	Dec. 31, 2013 CenterPoint Energy [Member]	Sep. 30, 2014 Revolving Credit Facility [Member]	Dec. 31, 2013 Revolving Credit Facility [Member]	Sep. 30, 2014 Letter of Credit [Member]	Dec. 31, 2013 Letter of Credit [Member]	Sep. 30, 2014 Line of Credit [Member]	Sep. 30, 2014 Line of Credit [Member] London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 600
Debt Instrument, Interest Rate, Stated Percentage			4.50%		5.60%			4.25%	4.25%
Debt Instrument, Repurchase Amount					56
Extinguishment of Debt, Amount						84	44
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed				101.00%		100.00%	101.00%
Line of Credit Facility, Maximum Borrowing Capacity	300	300
Line of Credit Facility, Interest Rate Description																	1.125%
Loans Outstanding												0	0	4	4
Percentage on limitation of debt to total capitalization under covenant (in hundredths)																65.00%
General mortgage bonds used as collateral	$ 408	$ 408								$ 290	$ 290