XML 107 R88.htm IDEA: XBRL DOCUMENT
v3.23.1

COMMITMENTS AND CONTINGENCIES - Guarantees and Indemnifications (Details) $ in Millions | Mar. 31, 2023 USD ($) | Jan. 31, 2022 USD ($) letterOfCredit | Sep. 16, 2020 USD ($)
--- | --- | --- | ---
Guarantor Obligations [Line Items] |  |  |
Number of letters of credit | letterOfCredit |  | 2 |
Letters of Credit | Eversource Investment LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum borrowing capacity |  |  | $ 25.0
North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Ownership interest (percent) | 50.00% |  |
Sunrise Wind LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 838.4 |  |
Ownership interest (percent) | 50.00% |  |
Revolution Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 547.1 |  |
Ownership interest (percent) | 50.00% |  |
South Fork Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 7.1 |  |
Ownership interest (percent) | 50.00% |  |
South Fork Wind, LLC | Letters of Credit |  |  |
Guarantor Obligations [Line Items] |  |  |
Amount outstanding under line of credit |  | $ 4.3 |
Eversource Investment LLC | North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Ownership interest (percent) | 50.00% |  |
Construction-related purchase agreements with third-party contractors | South Fork Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 207.7 |  |
Ownership interest (percent) | 50.00% |  |
Construction-related purchase agreements with third-party contractors | North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 726.2 |  |
Construction-related purchase agreements with third-party contractors | Sunrise Wind LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 668.6 |  |
Construction-related purchase agreements with third-party contractors | Revolution Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 409.7 |  |
Construction-related purchase agreements with third-party contractors | South Fork Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 126.2 |  |
Funding and indemnification obligations of North East Offshore LLC | Eversource Investment LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 68.9 |  |
Funding and indemnification obligations of North East Offshore LLC | Eversource Investment LLC | North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 910.0 |  |
Power Purchase Agreement | South Fork Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 7.1 |  |
OREC capacity production | Sunrise Wind LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 15.4 |  |
Ownership interest (percent) | 50.00% |  |
OREC capacity production | Sunrise Wind LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 11.0 |  |
Real estate purchase | Bay State Wind LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 2.5 |  |
Transmission interconnection | South Fork Wind, LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 1.2 |  |
Letters of Credit | Eversource Investment LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 4.3 |  |
Surety bonds | Various |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 37.2 |  |
Lease payments for real estate | Eversource Service |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | 0.4 |  |
Performance guarantee | North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 1,300.0 |  |
Percent of obligations guaranteed | 50.00% |  |
Payment guarantee | North East Offshore LLC |  |  |
Guarantor Obligations [Line Items] |  |  |
Maximum exposure (up to) | $ 62.5 |  |
Percent of obligations guaranteed | 50.00% |  |

X
- Definition Guarantor Obligations, Maximum Exposure, Percent Of Obligation + References No definition available. + Details
Name: | es_GuarantorObligationsMaximumExposurePercentOfObligation
Namespace Prefix: | es_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Letters Of Credit Issued + References No definition available. + Details
Name: | es_NumberOfLettersOfCreditIssued
Namespace Prefix: | es_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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_GuaranteeObligationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 + Details
Name: | us-gaap_LineOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=es_NortheastOffshoreLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=es_SunriseWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=es_RevolutionWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=es_SouthForkWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_SouthForkWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_EversourceInvestmentLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=es_PurchaseGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_NortheastOffshoreLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_SunriseWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_RevolutionWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_IndemnificationGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=es_PowerPurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=es_CapacityProductionGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=es_RealEstatePurchaseGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_BayStateWindLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=es_TransmissionInterconnectionGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_LetterOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_SuretyBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_VariousEntitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_PropertyLeaseGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=es_RockyRiverRealtyCompanyAndEversourceServiceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_PerformanceGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_PaymentGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |