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REGULATORY ACCOUNTING - Narrative (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | $ 236.1 | $ 221.0
Regulatory costs | 105.4 | 92.5
CL&P |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | 124.9 | 116.3
Regulatory costs | 55.8 | 47.2
NSTAR Electric |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | 44.1 | 41.1
Regulatory costs | 28.2 | 24.4
PSNH |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | $ 5.7 | $ 4.5

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- Definition Deferred Regulatory Costs + References No definition available. + Details
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- Definition Amount of regulatory costs not yet approved by the regulatory authority. + 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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Namespace Prefix: |
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- Details
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