Short-Term Borrowing (Details) - USD ($)	1 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Commercial paper, outstanding	$ 1,741,000,000	$ 1,741,000,000	$ 577,000,000
Weighted average interest rate		3.00%	1.80%
Loans outstanding under credit agreement	0	$ 0	$ 0
Letters of credit outstanding	$ 0	$ 0
Maximum ratio of consolidated debt to consolidated total capital	0.53	0.53
Minimum percentage of liens on assets	5.00%	5.00%
Failure to pay, maximum aggregate limit	$ 150,000,000	$ 150,000,000
Term Loan
Short-term Debt [Line Items]
Short-term borrowings	$ 825,000,000	$ 825,000,000
Debt term	6 months
Maximum
Short-term Debt [Line Items]
Maximum ratio of consolidated debt to consolidated total capital	0.65	0.65
Revolving Credit
Short-term Debt [Line Items]
Maximum borrowing capacity	$ 1,500,000,000	$ 1,500,000,000
Current amount available	1,000,000,000	1,000,000,000
Letters of Credit
Short-term Debt [Line Items]
Maximum borrowing capacity	1,200,000,000	1,200,000,000
CECONY
Short-term Debt [Line Items]
Commercial paper, outstanding	$ 1,192,000,000	$ 1,192,000,000	$ 150,000,000
Weighted average interest rate		3.00%	1.80%
Maximum ratio of consolidated debt to consolidated total capital	0.54	0.54
CECONY \| Revolving Credit
Short-term Debt [Line Items]
Maximum borrowing capacity	$ 2,250,000,000	$ 2,250,000,000

Debt Instrument, Covenant Compliance, Maximum Aggregate Limit Of Failure To Pay Debt Or Derivative Obligations

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Percentage Of Liens Of Companies Consolidated Asset

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Weighted Average Interest Rate Of Commercial Paper

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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.

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Carrying value as of the balance sheet date of portion of long-term loans payable due within one year or the operating cycle if longer.

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The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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Indebtedness divided by net capital.

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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.

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