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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 470
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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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SHORT-TERM AND LONG-TERM DEBT - Summary of Long-Term Debt Issuance and Repayments (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Mar. 31, 2022	Feb. 28, 2022	Mar. 31, 2022	Mar. 31, 2021
Debt Instrument [Line Items]
Repayments			$ (770,000)	$ (572,000)
Yankee Gas \| First Mortgage \| Yankee Gas 8.48% Series B First Mortgage Bonds
Debt Instrument [Line Items]
Interest rate, stated percentage	8.48%		8.48%
Repayments	$ (20,000)
Eversource Parent \| Senior Notes \| Eversource Parent 2.90% Series V Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage		2.90%
Issuances		$ 650,000
Eversource Parent \| Senior Notes \| Eversource Parent 3.38% Series W Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage		3.38%
Issuances		$ 650,000
Eversource Parent \| Senior Notes \| Eversource Parent 2.75% Series K Senior Notes
Debt Instrument [Line Items]
Interest rate, stated percentage	2.75%		2.75%
Repayments	$ (750,000)