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

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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

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

+ References

No definition available.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Capitalization - Long-term Debt, Additional Information (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Non-recourse debt		$ 2,076,000,000	$ 915,000,000
Short-term debt		825,000,000	0
Long-term debt		18,145,000,000	16,029,000,000
Transition Bonds Issued in 2004
Debt Instrument [Line Items]
Long-term debt		2,000,000	7,000,000
PG&E Project
Debt Instrument [Line Items]
Long-term debt		1,050,000,000
PG&E Project \| Scenario, Forecast
Debt Instrument [Line Items]
Short-term debt	$ 1,050,000,000
CECONY
Debt Instrument [Line Items]
Long-term debt		14,151,000,000	13,265,000,000
CECONY \| Tax-Exempt Debt
Debt Instrument [Line Items]
Debt instrument, face amount		450,000,000
Long-term debt		$ 450,000,000	$ 1,086,000,000