XML 114 R86.htm IDEA: XBRL DOCUMENT
v3.25.0.1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of AFUDC and Weighted Average AFUDC (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Components of Other Operating Costs and Expense [Line Items] |  |  |
Borrowed Funds | $ 64.4 | $ 44.6 | $ 21.8
Equity Funds | 97.8 | 78.1 | 47.3
Total AFUDC | $ 162.2 | $ 122.7 | $ 69.1
Average AFUDC Rate (in percent) | 6.50% | 5.80% | 4.70%
CL&P |  |  |
Components of Other Operating Costs and Expense [Line Items] |  |  |
Borrowed Funds | $ 8.1 | $ 7.7 | $ 4.8
Equity Funds | 22.4 | 20.0 | 13.6
Total AFUDC | $ 30.5 | $ 27.7 | $ 18.4
Average AFUDC Rate (in percent) | 6.70% | 6.70% | 6.60%
NSTAR Electric |  |  |
Components of Other Operating Costs and Expense [Line Items] |  |  |
Borrowed Funds | $ 27.2 | $ 17.2 | $ 10.7
Equity Funds | 58.8 | 45.7 | 24.6
Total AFUDC | $ 86.0 | $ 62.9 | $ 35.3
Average AFUDC Rate (in percent) | 7.00% | 5.90% | 5.40%
PSNH |  |  |
Components of Other Operating Costs and Expense [Line Items] |  |  |
Borrowed Funds | $ 8.9 | $ 6.1 | $ 1.4
Equity Funds | 7.0 | 5.4 | 2.5
Total AFUDC | $ 15.9 | $ 11.5 | $ 3.9
Average AFUDC Rate (in percent) | 5.50% | 5.10% | 2.60%

X
- Definition Total value of the public utilities allowance for funds used during construction capitalized portions, including both the equity and debt portions + References No definition available. + Details
Name: | es_AllowanceForFundsUsedDuringConstruction
Namespace Prefix: | es_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition [Line Items] for Components of Other Operating Costs and Expense [Table] + References No definition available. + Details
Name: | es_ComponentsofOtherOperatingCostsandExpenseLineItems
Namespace Prefix: | es_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478698/980-835-25-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479123/980-835-45-1 + Details
Name: | us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount capitalized of allowance for funds used during construction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478698/980-835-25-1 + Details
Name: | us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478698/980-835-25-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479123/980-835-45-1 + Details
Name: | us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
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: |