XML 82 R63.htm IDEA: XBRL DOCUMENT
v3.23.3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Components of Other Income, Net (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | $ 79,123 | $ 89,831 | $ 262,980 | $ 255,253
Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 28,500 | 55,300 | 96,600 | 164,500
AFUDC Equity |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 21,000 | 12,600 | 55,500 | 33,700
Equity in Earnings of Unconsolidated Affiliates |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 2,700 | 3,800 | 11,500 | 20,800
Investment (Loss)/Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 2,700 | 1,300 | (400) | 2,400
Interest Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 24,100 | 14,100 | 68,600 | 30,300
Other |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 100 | 2,700 | 31,200 | 3,600
Equity in Earnings |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Unrealized gain associated with investment |  |  |  | 12,200
CL&P |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 18,311 | 21,927 | 46,610 | 61,290
CL&P | Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 7,000 | 16,200 | 24,900 | 48,300
CL&P | AFUDC Equity |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 5,200 | 3,700 | 13,900 | 9,300
CL&P | Equity in Earnings of Unconsolidated Affiliates |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 0 | 0 | 0 | 0
CL&P | Investment (Loss)/Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 1,500 | 200 | (200) | (900)
CL&P | Interest Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 4,600 | 1,800 | 8,000 | 4,600
CL&P | Other |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 0 | 0 | 0 | 0
NSTAR Electric |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 39,908 | 37,895 | 120,690 | 101,385
NSTAR Electric | Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 12,900 | 21,600 | 41,700 | 64,000
NSTAR Electric | AFUDC Equity |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 12,500 | 6,500 | 34,000 | 17,500
NSTAR Electric | Equity in Earnings of Unconsolidated Affiliates |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 100 | 100 | 300 | 200
NSTAR Electric | Investment (Loss)/Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 700 | 400 | 500 | 600
NSTAR Electric | Interest Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 13,600 | 9,200 | 44,000 | 18,800
NSTAR Electric | Other |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 100 | 100 | 200 | 300
PSNH |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 7,180 | 8,073 | 19,199 | 23,365
PSNH | Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 3,700 | 6,800 | 11,800 | 20,100
PSNH | AFUDC Equity |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 1,600 | 700 | 3,400 | 1,700
PSNH | Equity in Earnings of Unconsolidated Affiliates |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 0 | 0 | 0 | 0
PSNH | Investment (Loss)/Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 400 | 200 | 0 | 500
PSNH | Interest Income |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | 1,500 | 400 | 3,600 | 1,100
PSNH | Other |  |  |  |
Summary of Accounting Policies [Line Items] |  |  |  |
Other income, net | $ 0 | $ 0 | $ 400 | $ 0

X
- Definition [Line Items] for Summary of Accounting Policies [Table] + References No definition available. + Details
Name: | es_SummaryofAccountingPoliciesLineItems
Namespace Prefix: | es_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481664/323-10-45-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-22 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 + Details
Name: | us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_NonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_NonServiceCostBenefitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_AFUDCEquityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_EquityinEarningsLossOfUnconsolidatedAffiliateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_InvestmentIncomeLossMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_InterestIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_OtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=es_EquityInEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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: |