Credit Exposure Independent System Operators

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- Definition

Credit exposure nonrated counterparties

+ References

No definition available.

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- Definition

Maximum Potential Future Exposure On Credit Risk Derivatives With Commodity Exchange Brokers

+ References

No definition available.

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- Definition

Maximum Potential Future Exposure On Credit Risk Derivatives With Investment Grade Counterparties

+ References

No definition available.

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- Definition

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5708775-113959

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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-Section 50
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fixed interest rate related to the interest rate derivative.

+ 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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Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment Holdings [Line Items]
Energy supply and hedging activities credit exposure total	$ 107
Makeup of net credit exposure independent system operators	44
Makeup of net credit exposure with investment-grade counterparties	25
Makeup of net credit exposure non-investment grade/non-rated counterparties	22
Makeup of net credit exposure with commodity exchange brokers	16
CECONY
Investment Holdings [Line Items]
Energy supply and hedging activities credit exposure total	17
Makeup of net credit exposure with investment-grade counterparties	10
Makeup of net credit exposure with commodity exchange brokers	7
Clean Energy Businesses \| Coram \| Interest Rate Swap
Investment Holdings [Line Items]
Derivative, fixed interest rate			2.0855%
Derivative asset	$ 1	$ 0