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DERIVATIVE INSTRUMENTS - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 USD ($) MW | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) MW | Sep. 30, 2023 USD ($) | Dec. 31, 2023 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 | 615 |  | 615 |  | 682
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 | $ | $ 0.5 | $ 1.5 | $ 3.4 | $ 1.6 |

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- Definition Amount of Capacity Provided Under Capacity Contract + References No definition available. + Details
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- Definition Derivative Instruments Gain (Loss) Recognized In Regulatory Asset Liability + References No definition available. + Details
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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. + Details
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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. + Details
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- Details
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