SHORT-TERM DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Line of Credit Facility [Line Items]
Borrowings Outstanding	$ 1,442,200	$ 1,505,450
Eversource Parent Commercial Paper Program
Line of Credit Facility [Line Items]
Borrowings Outstanding	1,442,200	1,342,950
Commercial Paper \| Eversource Parent Commercial Paper Program
Line of Credit Facility [Line Items]
Borrowings Outstanding	1,442,200	1,343,000
Available Borrowing Capacity	$ 557,800	$ 657,000
Weighted-Average Interest Rate (as a percentage)	4.63%	0.31%
Commercial Paper \| NSTAR Electric
Line of Credit Facility [Line Items]
Borrowings Outstanding	$ 0	$ 162,500
Available Borrowing Capacity	$ 650,000	$ 487,500
Weighted-Average Interest Rate (as a percentage)	0.00%	0.14%

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.

No definition available.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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