Capacity Available Under Preferred Stock Provisions

No definition available.

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- Definition

Debt Instrument, Term Extended

+ References

No definition available.

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- Definition

Line of Credit Facility, Amount Outstanding During Period

+ References

No definition available.

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- Definition

Percentage of Total Capitalization

+ References

No definition available.

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- Definition

Period of Maturity Restricting Provisions of Debt

+ References

No definition available.

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- Definition

Short-Term Borrowing Limit Approved By Regulatory Agency

+ References

No definition available.

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- References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
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-Name Accounting Standards Codification
-Section S99
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
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- 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
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
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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.

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SHORT-TERM DEBT - Narrative (Details) - USD ($)		12 Months Ended
SHORT-TERM DEBT - Narrative (Details) - USD ($)	Oct. 11, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 12, 2025
Commercial Paper \| Eversource
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 2,000,000,000.00
Line of Credit \| Eversource
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 2,000,000,000.00
Debt instrument term (in years)		5 years
Debt Instrument, Term Extended	1 year
CL&P
Short-term Debt [Line Items]
Short-term borrowing limit approved by regulatory agency				$ 600,000,000
Notes Payable		$ 0	$ 280,000,000
CL&P \| Related Party
Short-term Debt [Line Items]
Notes Payable			280,000,000.0
CL&P \| Unsecured Debt
Short-term Debt [Line Items]
Period of maturity restricting provisions of debt		10 years
Total capitalization (as a percentage)		10.00%
Capacity available under preferred stock provisions		$ 1,190,000,000
CL&P \| Line of Credit
Short-term Debt [Line Items]
Maximum borrowing capacity		375,000,000
Borrowings outstanding		0
NSTAR Electric
Short-term Debt [Line Items]
Short-term borrowing limit approved by regulatory agency				$ 655,000,000
Notes Payable		245,445,000	504,782,000
NSTAR Electric \| Commercial Paper
Short-term Debt [Line Items]
Maximum borrowing capacity		650,000,000
NSTAR Electric \| Line of Credit
Short-term Debt [Line Items]
Maximum borrowing capacity		$ 650,000,000
Debt instrument term (in years)		5 years
Debt Instrument, Term Extended	1 year
PSNH
Short-term Debt [Line Items]
Short-term borrowing limit approved by regulatory agency		$ 572,900,000
Notes Payable		49,300,000	131,100,000
PSNH \| Related Party
Short-term Debt [Line Items]
Notes Payable		$ 49,300,000	131,100,000
PSNH \| Short Term Debt Authorization Calculation
Short-term Debt [Line Items]
Interest Rate		10.00%
Short-term debt borrowing calculation approved by regulatory agency		$ 60,000,000
PSNH \| Line of Credit
Short-term Debt [Line Items]
Maximum borrowing capacity		250,000,000
Borrowings outstanding		0
Eversource Parent Company and Nstar Electric Company \| Line of Credit
Short-term Debt [Line Items]
Amount outstanding during period		$ 0	$ 0