Consecutive Period for System Restoration Costs to Exceed $100 million (in months)

No definition available.

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- Definition

Letters of credit swing line sublimit

+ References

No definition available.

+ Details

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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

Temporary increased percentage on limitation of debt to total capitalization under covenant (in hundredths)

+ References

No definition available.

+ Details

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- Definition

The minimum amount of estimated restoration cost in a calendar year in order for a temporary increase in debt to EBITDA 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.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

+ Details

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Period Type:	instant

- 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

+ Details

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Period Type:	instant

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Short-term Borrowings and Long-term Debt - Schedule of Revolving Credit Facilities (Details)	12 Months Ended
	Dec. 31, 2021 USD ($)	Feb. 28, 2021 USD ($)	Jan. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Size of credit facility	$ 4,000,000,000
Houston Electric
Debt Instrument [Line Items]
Size of credit facility	300,000,000
CERC Corp
Debt Instrument [Line Items]
Size of credit facility	$ 900,000,000
Line of Credit \| Houston Electric
Debt Instrument [Line Items]
Percentage on limitation of debt to total capitalization under covenant (in hundredths)	67.50%
Ratio of indebtedness to net capital	0.562
Line of Credit \| CERC Corp
Debt Instrument [Line Items]
Percentage on limitation of debt to total capitalization under covenant (in hundredths)	65.00%
Ratio of indebtedness to net capital	0.606
Line of Credit \| London Interbank Offered Rate (LIBOR) \| Houston Electric
Debt Instrument [Line Items]
Basis spread on LIBOR (as a percent)	1.375%
Line of Credit \| London Interbank Offered Rate (LIBOR) \| CERC Corp
Debt Instrument [Line Items]
Basis spread on LIBOR (as a percent)	1.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Loans	$ 0			$ 0
Revolving Credit Facility \| Houston Electric
Debt Instrument [Line Items]
Loans	0			0
Revolving Credit Facility \| CERC Corp
Debt Instrument [Line Items]
Loans	0			0
Letter of Credit
Debt Instrument [Line Items]
Loans	11,000,000			11,000,000
Letter of Credit \| Houston Electric
Debt Instrument [Line Items]
Loans	0			0
Letter of Credit \| CERC Corp
Debt Instrument [Line Items]
Loans	0			0
Commercial paper
Debt Instrument [Line Items]
Loans	2,649,000,000			1,517,000,000
Commercial paper \| Houston Electric
Debt Instrument [Line Items]
Loans	$ 0			$ 0
Weighted average interest rate (as a percent)	0.00%			0.00%
Commercial paper \| CERC Corp
Debt Instrument [Line Items]
Loans	$ 899,000,000			$ 347,000,000
Weighted average interest rate (as a percent)	0.26%			0.23%
Parent Company
Debt Instrument [Line Items]
Size of credit facility	$ 2,400,000,000	$ 2,400,000,000	$ 3,300,000,000
Parent Company \| Line of Credit
Debt Instrument [Line Items]
Percentage on limitation of debt to total capitalization under covenant (in hundredths)	65.00%
Ratio of indebtedness to net capital	0.618
Percentage on limitation of debt to total capitalization under covenant amended (in hundredths)	70.00%
Expected restoration costs	$ 100,000,000
Consecutive period for system restoration costs to exceed $100 million (in months)	12
Parent Company \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on LIBOR (as a percent)	1.625%
Parent Company \| Revolving Credit Facility
Debt Instrument [Line Items]
Loans	$ 0			$ 0
Parent Company \| Letter of Credit
Debt Instrument [Line Items]
Loans	11,000,000			11,000,000
Parent Company \| Commercial paper
Debt Instrument [Line Items]
Loans	$ 1,400,000,000			$ 1,078,000,000
Weighted average interest rate (as a percent)	0.34%			0.23%
VUHI
Debt Instrument [Line Items]
Size of credit facility	$ 400,000,000
Letters of credit swing line sublimit	$ 20,000,000
VUHI \| Line of Credit
Debt Instrument [Line Items]
Percentage on limitation of debt to total capitalization under covenant (in hundredths)	65.00%
Ratio of indebtedness to net capital	0.489
VUHI \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on LIBOR (as a percent)	1.25%
VUHI \| Revolving Credit Facility
Debt Instrument [Line Items]
Loans	$ 0			$ 0
VUHI \| Letter of Credit
Debt Instrument [Line Items]
Loans	0			0
VUHI \| Commercial paper
Debt Instrument [Line Items]
Loans	$ 350,000,000			$ 92,000,000
Weighted average interest rate (as a percent)	0.21%			0.22%