Amount of Capacity Provided Under Capacity Contract

No definition available.

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- Definition

Derivative Instruments Gain (Loss) Recognized In Regulatory Asset Liability

+ References

No definition available.

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- Definition

Percentage of Costs Or Benefits Borne Under Capacity-Related Contracts

+ References

No definition available.

+ Details

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- Definition

Percentage Of Costs Or Benefits Borne Under Capacity-Related Contracts By United Illuminated Company

+ 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

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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DERIVATIVE INSTRUMENTS - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
DERIVATIVE INSTRUMENTS - Narrative (Details) $ in Millions	Jul. 31, 2025 USD ($)	Jun. 30, 2025 USD ($) MW	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) MW	Jun. 30, 2024 USD ($)	Dec. 31, 2024 MW
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Percentage of costs or benefits borne under capacity-related contracts by united Illuminated Company (in percent)				20.00%
Amount of power to be purchased under capacity-related contract (in MW) \| MW		609		609		610
CL&P
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Percentage of costs or benefits borne under capacity-related contracts (in percent)				80.00%
Derivative instruments losses recognized in regulatory asset liability		$ 0.3	$ 1.9	$ 0.6	$ 2.9
NSTAR Electric \| Subsequent Event
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, term of contract	20 years
Derivative, notional amount	$ 6,700.0