XML 90 R68.htm IDEA: XBRL DOCUMENT
v3.24.3

REGULATORY ACCOUNTING - Narrative (Details) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | $ 216.6 | $ 241.7
Regulatory costs | 86.3 | 82.1
CL&P |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | 115.9 | 166.7
Regulatory costs | 46.7 | 64.0
NSTAR Electric |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | 39.1 | 21.9
Regulatory costs | 21.5 | 7.3
PSNH |  |
Regulatory Assets [Line Items] |  |
Amount of regulatory costs not yet approved | $ 2.6 | $ 1.2

X
- Definition Deferred Regulatory Costs + References No definition available. + Details
Name: | es_DeferredRegulatoryCosts
Namespace Prefix: | es_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of regulatory costs not yet approved by the regulatory authority. + References No definition available. + Details
Name: | us-gaap_AmountOfRegulatoryCostsNotYetApproved
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | us-gaap_RegulatoryAssetLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=es_TheConnecticutLightAndPowerCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=es_NstarElectricCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=es_PublicServiceCompanyOfNewHampshirePSNHMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |