Long-Term Debt, Current Maturities Classified As Noncurrent

No definition available.

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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.

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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

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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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
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Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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SHORT-TERM AND LONG-TERM DEBT - Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2025	Jul. 01, 2025	May 27, 2025	Mar. 26, 2025	Dec. 31, 2024
Line of Credit Facility [Line Items]
Long-term debt	$ 26,212,992,000				$ 25,701,627,000
Subsequent Event
Line of Credit Facility [Line Items]
Long-term debt, current maturities classified as noncurrent		$ 75,000,000.0
NSTAR Electric
Line of Credit Facility [Line Items]
Long-term debt	5,338,057,000				4,844,920,000
CL&P
Line of Credit Facility [Line Items]
Long-term debt	5,108,529,000				5,108,173,000
Notes payable to Eversource parent	0				280,000,000
CL&P \| Related Party
Line of Credit Facility [Line Items]
Notes payable to Eversource parent					280,000,000.0
PSNH
Line of Credit Facility [Line Items]
Long-term debt	2,031,083,000				1,732,066,000
Notes payable to Eversource parent	35,300,000				131,100,000
PSNH \| Related Party
Line of Credit Facility [Line Items]
Notes payable to Eversource parent	35,300,000				131,100,000
Line of Credit \| CL&P
Line of Credit Facility [Line Items]
Maximum borrowing capacity	375,000,000
Amount outstanding under line of credit	0				0
Line of Credit \| PSNH
Line of Credit Facility [Line Items]
Maximum borrowing capacity	250,000,000		$ 300,000,000
Amount outstanding under line of credit	0				0
Line of Credit \| Yankee Gas
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 360,000,000
Commercial Paper \| NSTAR Electric
Line of Credit Facility [Line Items]
Maximum borrowing capacity	650,000,000.0
Commercial Paper \| Yankee Gas \| Subsequent Event
Line of Credit Facility [Line Items]
Long-term debt		$ 110,000,000.0
Line of Credit \| NSTAR Electric
Line of Credit Facility [Line Items]
Maximum borrowing capacity	650,000,000.0
Eversource Parent \| Commercial Paper
Line of Credit Facility [Line Items]
Maximum borrowing capacity	2,000,000,000.00
Eversource Parent \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 2,000,000,000
Debt instrument term (in years)	5 years
NSTAR Electric \| Line of Credit \| NSTAR Electric
Line of Credit Facility [Line Items]
Debt instrument term (in years)	5 years
NSTAR Electric and Eversource \| Line of Credit
Line of Credit Facility [Line Items]
Amount outstanding under line of credit	$ 0				$ 0